diff --git a/saju-lab/app/calculator/lucky.py b/saju-lab/app/calculator/lucky.py
new file mode 100644
index 0000000..e8d4867
--- /dev/null
+++ b/saju-lab/app/calculator/lucky.py
@@ -0,0 +1,84 @@
+"""오늘의 럭키 컬러/숫자/방향 + 행운/위험 알림."""
+from datetime import date as _date
+from typing import Dict, List
+
+import sxtwl
+
+from .constants import HEAVENLY_STEMS, EARTHLY_BRANCHES, FIVE_ELEMENTS, KE_CYCLE
+
+
+LUCKY_COLOR_BY_ELEMENT: Dict[str, List[str]] = {
+    "木": ["청록", "녹색"],
+    "火": ["빨강", "주황"],
+    "土": ["황색", "베이지"],
+    "金": ["흰색", "은색"],
+    "水": ["파랑", "검정"],
+}
+
+LUCKY_DIRECTION_BY_ELEMENT: Dict[str, str] = {
+    "木": "동쪽",
+    "火": "남쪽",
+    "土": "중앙",
+    "金": "서쪽",
+    "水": "북쪽",
+}
+
+
+def _day_stem_branch_idx(target: _date) -> tuple[int, int]:
+    """양력 → sxtwl 일주 천간/지지 인덱스."""
+    day_obj = sxtwl.fromSolar(target.year, target.month, target.day)
+    try:
+        gz = day_obj.getDayGZ()
+        return gz.tg, gz.dz
+    except AttributeError:
+        return day_obj.getDayTG(), day_obj.getDayDZ()
+
+
+def calculate_lucky(saju: dict, analysis: dict, target_date: _date) -> dict:
+    """오늘의 럭키 정보."""
+    yongshin = analysis["yong_shin"]["yong_shin"]
+    color = LUCKY_COLOR_BY_ELEMENT.get(yongshin, ["흰색"])
+    direction = LUCKY_DIRECTION_BY_ELEMENT.get(yongshin, "중앙")
+
+    # 럭키 숫자: 오늘 일진 천간+지지 인덱스 합 % 9 + 1 → 1~9
+    day_stem_idx, day_branch_idx = _day_stem_branch_idx(target_date)
+    number = (day_stem_idx + day_branch_idx) % 9 + 1
+
+    # 행운/위험
+    good_signs: List[str] = []
+    warnings: List[str] = []
+
+    today_stem = HEAVENLY_STEMS[day_stem_idx]
+    today_branch = EARTHLY_BRANCHES[day_branch_idx]
+    day_master = saju["day_stem"]
+
+    day_elem = FIVE_ELEMENTS[day_master]
+    today_elem = FIVE_ELEMENTS[today_stem]
+    if KE_CYCLE.get(day_elem) == today_elem:
+        good_signs.append("재물 기회가 다가옵니다")
+    if KE_CYCLE.get(today_elem) == day_elem:
+        warnings.append("강한 압박이 있을 수 있어요")
+
+    LIU_CHONG = {
+        frozenset(["子", "午"]), frozenset(["丑", "未"]),
+        frozenset(["寅", "申"]), frozenset(["卯", "酉"]),
+        frozenset(["辰", "戌"]), frozenset(["巳", "亥"]),
+    }
+    LIU_HE = {
+        frozenset(["子", "丑"]), frozenset(["寅", "亥"]),
+        frozenset(["卯", "戌"]), frozenset(["辰", "酉"]),
+        frozenset(["巳", "申"]), frozenset(["午", "未"]),
+    }
+    day_branch = saju["day"]["branch"]
+    if frozenset([day_branch, today_branch]) in LIU_CHONG:
+        warnings.append("대인 갈등에 주의하세요")
+    if frozenset([day_branch, today_branch]) in LIU_HE:
+        good_signs.append("좋은 인연을 만날 수 있어요")
+
+    return {
+        "color": color,
+        "number": number,
+        "direction": direction,
+        "good_signs": good_signs,
+        "warnings": warnings,
+    }
diff --git a/saju-lab/tests/test_lucky.py b/saju-lab/tests/test_lucky.py
new file mode 100644
index 0000000..59d1e88
--- /dev/null
+++ b/saju-lab/tests/test_lucky.py
@@ -0,0 +1,63 @@
+from datetime import date
+
+import pytest
+
+from app.calculator.core import calculate_saju
+from app.calculator.analysis import perform_full_analysis
+from app.calculator.lucky import calculate_lucky
+
+
+def _saju_for(year, month, day, hour, gender):
+    saju = calculate_saju(year, month, day, hour, gender)
+    analysis = perform_full_analysis(saju, 2026)
+    return saju, analysis
+
+
+def test_lucky_keys():
+    saju, analysis = _saju_for(1990, 5, 15, 14, "male")
+    r = calculate_lucky(saju, analysis, date(2026, 5, 26))
+    for k in ("color", "number", "direction", "good_signs", "warnings"):
+        assert k in r, f"missing {k}"
+
+
+def test_lucky_number_range():
+    saju, analysis = _saju_for(1990, 5, 15, 14, "male")
+    r = calculate_lucky(saju, analysis, date(2026, 5, 26))
+    assert 1 <= r["number"] <= 9
+
+
+def test_lucky_color_from_yongshin():
+    saju, analysis = _saju_for(1990, 5, 15, 14, "male")
+    r = calculate_lucky(saju, analysis, date(2026, 5, 26))
+    assert isinstance(r["color"], list)
+    assert len(r["color"]) >= 1
+    yongshin = analysis["yong_shin"]["yong_shin"]
+    valid_colors_by_element = {
+        "木": {"청록", "녹색"},
+        "火": {"빨강", "주황"},
+        "土": {"황색", "베이지"},
+        "金": {"흰색", "은색"},
+        "水": {"파랑", "검정"},
+    }
+    expected_set = valid_colors_by_element[yongshin]
+    assert all(c in expected_set for c in r["color"])
+
+
+def test_lucky_direction_from_yongshin():
+    saju, analysis = _saju_for(1990, 5, 15, 14, "male")
+    r = calculate_lucky(saju, analysis, date(2026, 5, 26))
+    valid_dirs = {"동쪽", "남쪽", "중앙", "서쪽", "북쪽"}
+    assert r["direction"] in valid_dirs
+
+
+def test_good_signs_and_warnings_are_lists():
+    saju, analysis = _saju_for(1990, 5, 15, 14, "male")
+    r = calculate_lucky(saju, analysis, date(2026, 5, 26))
+    assert isinstance(r["good_signs"], list)
+    assert isinstance(r["warnings"], list)
+
+
+def test_handles_missing_hour():
+    saju, analysis = _saju_for(1990, 5, 15, None, "male")
+    r = calculate_lucky(saju, analysis, date(2026, 5, 26))
+    assert 1 <= r["number"] <= 9