diff --git a/backend/app/api/__init__.py b/backend/app/api/__init__.py
index b2d2274..2387385 100644
--- a/backend/app/api/__init__.py
+++ b/backend/app/api/__init__.py
@@ -5,6 +5,7 @@ from app.api.strategy import router as strategy_router
 from app.api.market import router as market_router
 from app.api.backtest import router as backtest_router
 from app.api.snapshot import router as snapshot_router
+from app.api.data_explorer import router as data_explorer_router
 
 __all__ = [
     "auth_router",
@@ -14,4 +15,5 @@ __all__ = [
     "market_router",
     "backtest_router",
     "snapshot_router",
+    "data_explorer_router",
 ]
diff --git a/backend/app/api/data_explorer.py b/backend/app/api/data_explorer.py
new file mode 100644
index 0000000..ae17c27
--- /dev/null
+++ b/backend/app/api/data_explorer.py
@@ -0,0 +1,237 @@
+"""
+Data explorer API endpoints for viewing collected stock/ETF data.
+"""
+from datetime import date
+from decimal import Decimal
+from typing import Optional, List
+
+from fastapi import APIRouter, Depends, Query
+from sqlalchemy import or_
+from sqlalchemy.orm import Session
+from pydantic import BaseModel
+
+from app.core.database import get_db
+from app.api.deps import CurrentUser
+from app.models.stock import Stock, ETF, Price, ETFPrice, Sector, Valuation
+
+router = APIRouter(prefix="/api/data", tags=["data-explorer"])
+
+
+# --- Response schemas ---
+
+class PaginatedResponse(BaseModel):
+    items: list
+    total: int
+    page: int
+    size: int
+
+
+class StockItem(BaseModel):
+    ticker: str
+    name: str
+    market: str
+    close_price: Decimal | None = None
+    market_cap: int | None = None
+
+    class Config:
+        from_attributes = True
+
+
+class ETFItem(BaseModel):
+    ticker: str
+    name: str
+    asset_class: str
+    market: str
+    expense_ratio: Decimal | None = None
+
+    class Config:
+        from_attributes = True
+
+
+class PriceItem(BaseModel):
+    date: date
+    open: Decimal | None = None
+    high: Decimal | None = None
+    low: Decimal | None = None
+    close: Decimal
+    volume: int | None = None
+
+    class Config:
+        from_attributes = True
+
+
+class ETFPriceItem(BaseModel):
+    date: date
+    close: Decimal
+    nav: Decimal | None = None
+    volume: int | None = None
+
+    class Config:
+        from_attributes = True
+
+
+class SectorItem(BaseModel):
+    ticker: str
+    company_name: str
+    sector_code: str
+    sector_name: str
+
+    class Config:
+        from_attributes = True
+
+
+class ValuationItem(BaseModel):
+    ticker: str
+    base_date: date
+    per: Decimal | None = None
+    pbr: Decimal | None = None
+    psr: Decimal | None = None
+    pcr: Decimal | None = None
+    dividend_yield: Decimal | None = None
+
+    class Config:
+        from_attributes = True
+
+
+# --- Endpoints ---
+
+@router.get("/stocks")
+async def list_stocks(
+    current_user: CurrentUser,
+    db: Session = Depends(get_db),
+    page: int = Query(1, ge=1),
+    size: int = Query(50, ge=1, le=200),
+    search: Optional[str] = None,
+    market: Optional[str] = None,
+):
+    """List collected stocks with pagination and search."""
+    query = db.query(Stock)
+    if search:
+        query = query.filter(
+            or_(Stock.ticker.contains(search), Stock.name.contains(search))
+        )
+    if market:
+        query = query.filter(Stock.market == market)
+
+    total = query.count()
+    items = query.order_by(Stock.ticker).offset((page - 1) * size).limit(size).all()
+
+    return {
+        "items": [StockItem.model_validate(s) for s in items],
+        "total": total,
+        "page": page,
+        "size": size,
+    }
+
+
+@router.get("/stocks/{ticker}/prices")
+async def get_stock_prices(
+    ticker: str,
+    current_user: CurrentUser,
+    db: Session = Depends(get_db),
+):
+    """Get daily prices for a stock."""
+    prices = (
+        db.query(Price)
+        .filter(Price.ticker == ticker)
+        .order_by(Price.date.asc())
+        .all()
+    )
+    return [PriceItem.model_validate(p) for p in prices]
+
+
+@router.get("/etfs")
+async def list_etfs(
+    current_user: CurrentUser,
+    db: Session = Depends(get_db),
+    page: int = Query(1, ge=1),
+    size: int = Query(50, ge=1, le=200),
+    search: Optional[str] = None,
+):
+    """List collected ETFs with pagination and search."""
+    query = db.query(ETF)
+    if search:
+        query = query.filter(
+            or_(ETF.ticker.contains(search), ETF.name.contains(search))
+        )
+
+    total = query.count()
+    items = query.order_by(ETF.ticker).offset((page - 1) * size).limit(size).all()
+
+    return {
+        "items": [ETFItem.model_validate(e) for e in items],
+        "total": total,
+        "page": page,
+        "size": size,
+    }
+
+
+@router.get("/etfs/{ticker}/prices")
+async def get_etf_prices(
+    ticker: str,
+    current_user: CurrentUser,
+    db: Session = Depends(get_db),
+):
+    """Get daily prices for an ETF."""
+    prices = (
+        db.query(ETFPrice)
+        .filter(ETFPrice.ticker == ticker)
+        .order_by(ETFPrice.date.asc())
+        .all()
+    )
+    return [ETFPriceItem.model_validate(p) for p in prices]
+
+
+@router.get("/sectors")
+async def list_sectors(
+    current_user: CurrentUser,
+    db: Session = Depends(get_db),
+    page: int = Query(1, ge=1),
+    size: int = Query(50, ge=1, le=200),
+    search: Optional[str] = None,
+):
+    """List sector classification data."""
+    query = db.query(Sector)
+    if search:
+        query = query.filter(
+            or_(Sector.ticker.contains(search), Sector.company_name.contains(search), Sector.sector_name.contains(search))
+        )
+
+    total = query.count()
+    items = query.order_by(Sector.ticker).offset((page - 1) * size).limit(size).all()
+
+    return {
+        "items": [SectorItem.model_validate(s) for s in items],
+        "total": total,
+        "page": page,
+        "size": size,
+    }
+
+
+@router.get("/valuations")
+async def list_valuations(
+    current_user: CurrentUser,
+    db: Session = Depends(get_db),
+    page: int = Query(1, ge=1),
+    size: int = Query(50, ge=1, le=200),
+    search: Optional[str] = None,
+):
+    """List valuation metrics data."""
+    query = db.query(Valuation)
+    if search:
+        query = query.filter(Valuation.ticker.contains(search))
+
+    total = query.count()
+    items = (
+        query.order_by(Valuation.ticker, Valuation.base_date.desc())
+        .offset((page - 1) * size)
+        .limit(size)
+        .all()
+    )
+
+    return {
+        "items": [ValuationItem.model_validate(v) for v in items],
+        "total": total,
+        "page": page,
+        "size": size,
+    }
diff --git a/backend/app/main.py b/backend/app/main.py
index 081b8f4..a19a059 100644
--- a/backend/app/main.py
+++ b/backend/app/main.py
@@ -9,7 +9,7 @@ from fastapi.middleware.cors import CORSMiddleware
 
 from app.api import (
     auth_router, admin_router, portfolio_router, strategy_router,
-    market_router, backtest_router, snapshot_router,
+    market_router, backtest_router, snapshot_router, data_explorer_router,
 )
 
 # Configure logging
@@ -111,6 +111,7 @@ app.include_router(strategy_router)
 app.include_router(market_router)
 app.include_router(backtest_router)
 app.include_router(snapshot_router)
+app.include_router(data_explorer_router)
 
 
 @app.get("/health")
diff --git a/backend/tests/e2e/test_data_explorer.py b/backend/tests/e2e/test_data_explorer.py
new file mode 100644
index 0000000..c7d884a
--- /dev/null
+++ b/backend/tests/e2e/test_data_explorer.py
@@ -0,0 +1,93 @@
+"""
+E2E tests for data explorer API.
+"""
+from datetime import date
+from fastapi.testclient import TestClient
+from sqlalchemy.orm import Session
+
+from app.models.stock import Stock, ETF, Price, ETFPrice, Sector, Valuation, AssetClass
+
+
+def _seed_stock(db: Session):
+    """Add test stock data."""
+    stock = Stock(
+        ticker="005930", name="삼성전자", market="KOSPI",
+        close_price=70000, market_cap=400000000000000,
+        stock_type="common", base_date=date(2025, 1, 1),
+    )
+    db.add(stock)
+    db.add(Price(ticker="005930", date=date(2025, 1, 2), open=69000, high=71000, low=68500, close=70000, volume=10000000))
+    db.add(Price(ticker="005930", date=date(2025, 1, 3), open=70000, high=72000, low=69000, close=71000, volume=12000000))
+    db.commit()
+
+
+def _seed_etf(db: Session):
+    """Add test ETF data."""
+    etf = ETF(ticker="069500", name="TIGER 200", asset_class=AssetClass.EQUITY, market="ETF")
+    db.add(etf)
+    db.add(ETFPrice(ticker="069500", date=date(2025, 1, 2), close=43000, volume=500000))
+    db.add(ETFPrice(ticker="069500", date=date(2025, 1, 3), close=43500, volume=600000))
+    db.commit()
+
+
+def _seed_sector(db: Session):
+    db.add(Sector(ticker="005930", sector_code="G45", company_name="삼성전자", sector_name="반도체", base_date=date(2025, 1, 1)))
+    db.commit()
+
+
+def _seed_valuation(db: Session):
+    db.add(Valuation(ticker="005930", base_date=date(2025, 1, 1), per=12.5, pbr=1.3, dividend_yield=2.1))
+    db.commit()
+
+
+def test_list_stocks(client: TestClient, auth_headers, db: Session):
+    _seed_stock(db)
+    resp = client.get("/api/data/stocks", headers=auth_headers)
+    assert resp.status_code == 200
+    data = resp.json()
+    assert data["total"] >= 1
+    assert len(data["items"]) >= 1
+    assert data["items"][0]["ticker"] == "005930"
+
+
+def test_list_stocks_search(client: TestClient, auth_headers, db: Session):
+    _seed_stock(db)
+    resp = client.get("/api/data/stocks?search=삼성", headers=auth_headers)
+    assert resp.status_code == 200
+    assert resp.json()["total"] >= 1
+
+
+def test_stock_prices(client: TestClient, auth_headers, db: Session):
+    _seed_stock(db)
+    resp = client.get("/api/data/stocks/005930/prices", headers=auth_headers)
+    assert resp.status_code == 200
+    data = resp.json()
+    assert len(data) == 2
+
+
+def test_list_etfs(client: TestClient, auth_headers, db: Session):
+    _seed_etf(db)
+    resp = client.get("/api/data/etfs", headers=auth_headers)
+    assert resp.status_code == 200
+    assert resp.json()["total"] >= 1
+
+
+def test_etf_prices(client: TestClient, auth_headers, db: Session):
+    _seed_etf(db)
+    resp = client.get("/api/data/etfs/069500/prices", headers=auth_headers)
+    assert resp.status_code == 200
+    assert len(resp.json()) == 2
+
+
+def test_list_sectors(client: TestClient, auth_headers, db: Session):
+    _seed_sector(db)
+    resp = client.get("/api/data/sectors", headers=auth_headers)
+    assert resp.status_code == 200
+    assert resp.json()["total"] >= 1
+
+
+def test_list_valuations(client: TestClient, auth_headers, db: Session):
+    _seed_valuation(db)
+    resp = client.get("/api/data/valuations", headers=auth_headers)
+    assert resp.status_code == 200
+    assert resp.json()["total"] >= 1