diff --git a/Dockerfile b/Dockerfile
index d0a5fce..e702b6d 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -15,6 +15,7 @@ RUN apt-get update && apt-get install -y --no-install-recommends \
     sg3-utils \
     lsscsi \
     util-linux \
+    ledmon \
     && rm -rf /var/lib/apt/lists/*
 
 WORKDIR /app
diff --git a/frontend/src/App.jsx b/frontend/src/App.jsx
index a5c5f95..a8360f6 100644
--- a/frontend/src/App.jsx
+++ b/frontend/src/App.jsx
@@ -353,11 +353,35 @@ function TableView({ enclosure, onSelect, selectedSerial, t }) {
 }
 
 function DriveDetail({ slot, onClose, t }) {
+  const [ledLoading, setLedLoading] = useState(false);
+  const [ledState, setLedState] = useState(null); // "locate" | "off" | null
+
   if (!slot) return null;
   const d = slot.drive || {};
   const healthStatus = d.health_status || "healthy";
   const c = t.health[healthStatus] || t.health.healthy;
 
+  const setLed = async (state) => {
+    setLedLoading(true);
+    try {
+      const res = await fetch(`${API_BASE}/api/drives/${slot.device}/led`, {
+        method: "POST",
+        headers: { "Content-Type": "application/json" },
+        body: JSON.stringify({ state }),
+      });
+      if (!res.ok) {
+        const err = await res.json().catch(() => ({}));
+        throw new Error(err.detail || `HTTP ${res.status}`);
+      }
+      setLedState(state);
+    } catch (err) {
+      console.error("LED control failed:", err);
+      setLedState(null);
+    } finally {
+      setLedLoading(false);
+    }
+  };
+
   const smartFields = [
     ["SMART Status", d.smart_healthy === true ? "PASSED" : d.smart_healthy === false ? "FAILED" : "Unknown"],
     ["Temperature", d.temperature_c != null ? `${d.temperature_c}\u00B0C` : "\u2014"],
@@ -504,7 +528,40 @@ function DriveDetail({ slot, onClose, t }) {
           })}
         </div>
 
-        <div style={{ padding: "12px 24px 20px", textAlign: "right" }}>
+        <div style={{ padding: "12px 24px 20px", display: "flex", alignItems: "center", justifyContent: "space-between" }}>
+          <div style={{ display: "flex", alignItems: "center", gap: 8 }}>
+            <button
+              onClick={() => setLed("locate")}
+              disabled={ledLoading}
+              style={{
+                background: ledState === "locate" ? t.health.warning.bg : t.btnBg,
+                border: `1px solid ${ledState === "locate" ? t.health.warning.border : t.cardBorder}`,
+                borderRadius: 10, padding: "8px 16px", fontSize: 13, fontWeight: 600,
+                cursor: ledLoading ? "wait" : "pointer",
+                color: ledState === "locate" ? t.health.warning.text : t.textSecondary,
+                transition: "all 0.15s", opacity: ledLoading ? 0.6 : 1,
+              }}
+              onMouseEnter={(e) => { if (!ledLoading) e.currentTarget.style.background = ledState === "locate" ? t.health.warning.bg : t.btnHover; }}
+              onMouseLeave={(e) => { e.currentTarget.style.background = ledState === "locate" ? t.health.warning.bg : t.btnBg; }}
+            >
+              {ledLoading && ledState !== "locate" ? "..." : "Locate"}
+            </button>
+            <button
+              onClick={() => setLed("off")}
+              disabled={ledLoading}
+              style={{
+                background: t.btnBg, border: `1px solid ${t.cardBorder}`,
+                borderRadius: 10, padding: "8px 16px", fontSize: 13, fontWeight: 600,
+                cursor: ledLoading ? "wait" : "pointer",
+                color: t.textSecondary, transition: "all 0.15s",
+                opacity: ledLoading ? 0.6 : 1,
+              }}
+              onMouseEnter={(e) => { if (!ledLoading) e.currentTarget.style.background = t.btnHover; }}
+              onMouseLeave={(e) => { e.currentTarget.style.background = t.btnBg; }}
+            >
+              {ledLoading && ledState === "locate" ? "..." : "LED Off"}
+            </button>
+          </div>
           <button
             onClick={onClose}
             style={{
diff --git a/main.py b/main.py
index f2f53fa..f621be9 100644
--- a/main.py
+++ b/main.py
@@ -8,7 +8,7 @@ from fastapi.responses import FileResponse
 from fastapi.staticfiles import StaticFiles
 
 from models.schemas import HealthCheck
-from routers import drives, enclosures, overview
+from routers import drives, enclosures, leds, overview
 from services.smart import sg_ses_available, smartctl_available
 
 logging.basicConfig(
@@ -32,6 +32,7 @@ app.add_middleware(
 
 app.include_router(enclosures.router)
 app.include_router(drives.router)
+app.include_router(leds.router)
 app.include_router(overview.router)
 
 _tool_status: dict[str, bool] = {}
diff --git a/routers/leds.py b/routers/leds.py
new file mode 100644
index 0000000..4ee8ec4
--- /dev/null
+++ b/routers/leds.py
@@ -0,0 +1,29 @@
+from fastapi import APIRouter, HTTPException
+from pydantic import BaseModel, field_validator
+
+from services.leds import set_led
+
+router = APIRouter(prefix="/api/drives", tags=["leds"])
+
+
+class LedRequest(BaseModel):
+    state: str
+
+    @field_validator("state")
+    @classmethod
+    def validate_state(cls, v: str) -> str:
+        if v not in ("locate", "off"):
+            raise ValueError("state must be 'locate' or 'off'")
+        return v
+
+
+@router.post("/{device}/led")
+async def set_drive_led(device: str, body: LedRequest):
+    """Set the locate LED for a drive."""
+    try:
+        result = await set_led(device, body.state)
+    except ValueError as e:
+        raise HTTPException(status_code=400, detail=str(e))
+    except RuntimeError as e:
+        raise HTTPException(status_code=502, detail=str(e))
+    return result
diff --git a/services/leds.py b/services/leds.py
new file mode 100644
index 0000000..7bb886b
--- /dev/null
+++ b/services/leds.py
@@ -0,0 +1,29 @@
+import asyncio
+import re
+
+
+async def set_led(device: str, state: str) -> dict:
+    """Set the locate LED on a drive via ledctl.
+
+    Args:
+        device: Block device name (e.g. "sda"). Must be alphanumeric.
+        state: "locate" to turn on the locate LED, "off" to turn it off.
+    """
+    if not re.fullmatch(r"[a-zA-Z0-9]+", device):
+        raise ValueError(f"Invalid device name: {device}")
+    if state not in ("locate", "off"):
+        raise ValueError(f"Invalid state: {state}")
+
+    proc = await asyncio.create_subprocess_exec(
+        "ledctl",
+        f"{state}=/dev/{device}",
+        stdout=asyncio.subprocess.PIPE,
+        stderr=asyncio.subprocess.PIPE,
+    )
+    stdout, stderr = await proc.communicate()
+
+    if proc.returncode != 0:
+        err = stderr.decode().strip() or stdout.decode().strip()
+        raise RuntimeError(f"ledctl failed (rc={proc.returncode}): {err}")
+
+    return {"device": device, "state": state}