diff --git a/electron/gateway/startup-recovery.ts b/electron/gateway/startup-recovery.ts
index cc4c3b02e..012e55ac4 100644
--- a/electron/gateway/startup-recovery.ts
+++ b/electron/gateway/startup-recovery.ts
@@ -22,6 +22,14 @@ const TRANSIENT_START_ERROR_PATTERNS: RegExp[] = [
   /Port \d+ still occupied after \d+ms/i,
 ];
 
+/**
+ * Patterns that indicate the gateway is already managed by systemd and cannot
+ * be started as a child process.  Retrying is pointless in this scenario.
+ */
+const SYSTEMD_CONFLICT_PATTERNS: RegExp[] = [
+  /already running under systemd/i,
+];
+
 function normalizeLogLine(value: string): string {
   return value.trim();
 }
@@ -75,6 +83,24 @@ export function isTransientGatewayStartError(error: unknown): boolean {
   return TRANSIENT_START_ERROR_PATTERNS.some((pattern) => pattern.test(errorText));
 }
 
+/**
+ * Returns true when the gateway stderr indicates it is already supervised by
+ * systemd.  In that case ClawX cannot own the process and retrying startup
+ * will only produce the same result.
+ */
+export function isSystemdConflictSignal(text: string): boolean {
+  const normalized = text.trim();
+  if (!normalized) return false;
+  return SYSTEMD_CONFLICT_PATTERNS.some((pattern) => pattern.test(normalized));
+}
+
+/**
+ * Returns true when any startup stderr line signals a systemd conflict.
+ */
+export function hasSystemdConflictSignal(startupStderrLines: string[]): boolean {
+  return startupStderrLines.some(isSystemdConflictSignal);
+}
+
 export type GatewayStartupRecoveryAction = 'repair' | 'retry' | 'fail';
 
 export function getGatewayStartupRecoveryAction(options: {
@@ -84,6 +110,13 @@ export function getGatewayStartupRecoveryAction(options: {
   attempt: number;
   maxAttempts: number;
 }): GatewayStartupRecoveryAction {
+  // If the gateway reports it's already managed by systemd, retrying will not
+  // help.  Fail immediately so the user gets a clear error state instead of
+  // a long retry loop.
+  if (hasSystemdConflictSignal(options.startupStderrLines)) {
+    return 'fail';
+  }
+
   if (shouldAttemptConfigAutoRepair(
     options.startupError,
     options.startupStderrLines,
diff --git a/electron/gateway/startup-stderr.ts b/electron/gateway/startup-stderr.ts
index 4be0a4615..c1adf1a90 100644
--- a/electron/gateway/startup-stderr.ts
+++ b/electron/gateway/startup-stderr.ts
@@ -38,6 +38,14 @@ export function classifyGatewayStderrMessage(message: string): GatewayStderrClas
     return { level: 'debug', normalized: msg };
   }
 
+  // The gateway binary reports this when it detects a systemd supervisor.
+  // ClawX will fail fast rather than retry, so downgrade to debug to avoid
+  // flooding the log with repeated identical lines during the (brief) window
+  // before the process exits.
+  if (msg.includes('already running under systemd')) {
+    return { level: 'debug', normalized: msg };
+  }
+
   return { level: 'warn', normalized: msg };
 }
 
diff --git a/tests/unit/gateway-startup-recovery.test.ts b/tests/unit/gateway-startup-recovery.test.ts
index 2692385ce..764b4fcb3 100644
--- a/tests/unit/gateway-startup-recovery.test.ts
+++ b/tests/unit/gateway-startup-recovery.test.ts
@@ -3,6 +3,9 @@ import {
   hasInvalidConfigFailureSignal,
   isInvalidConfigSignal,
   shouldAttemptConfigAutoRepair,
+  isSystemdConflictSignal,
+  hasSystemdConflictSignal,
+  getGatewayStartupRecoveryAction,
 } from '@electron/gateway/startup-recovery';
 
 describe('gateway startup recovery heuristics', () => {
@@ -48,5 +51,60 @@ describe('gateway startup recovery heuristics', () => {
     expect(isInvalidConfigSignal('Run: openclaw doctor --fix')).toBe(true);
     expect(isInvalidConfigSignal('Gateway ready after 3 attempts')).toBe(false);
   });
+
+  describe('systemd conflict detection', () => {
+    it('detects already-running-under-systemd signal', () => {
+      expect(isSystemdConflictSignal('2026-03-27T13:08:36.125+11:00 [gateway] already running under systemd; waiting 5000ms before retrying startup')).toBe(true);
+      expect(isSystemdConflictSignal('already running under systemd')).toBe(true);
+      expect(isSystemdConflictSignal('ALREADY RUNNING UNDER SYSTEMD')).toBe(true);
+    });
+
+    it('does not false-positive on unrelated messages', () => {
+      expect(isSystemdConflictSignal('Gateway process exited (code=1)')).toBe(false);
+      expect(isSystemdConflictSignal('WebSocket closed before handshake')).toBe(false);
+      expect(isSystemdConflictSignal('')).toBe(false);
+    });
+
+    it('hasSystemdConflictSignal returns true when any line matches', () => {
+      const lines = [
+        'Starting gateway...',
+        '[gateway] already running under systemd; waiting 5000ms before retrying startup',
+        'Retrying...',
+      ];
+      expect(hasSystemdConflictSignal(lines)).toBe(true);
+    });
+
+    it('hasSystemdConflictSignal returns false when no lines match', () => {
+      const lines = ['Gateway ready', 'Listening on port 18789'];
+      expect(hasSystemdConflictSignal(lines)).toBe(false);
+    });
+
+    it('getGatewayStartupRecoveryAction returns fail immediately on systemd conflict', () => {
+      const stderrLines = [
+        '[gateway] already running under systemd; waiting 5000ms before retrying startup',
+      ];
+      // Should fail even on the first attempt and even for an error that would
+      // normally be classified as transient.
+      const action = getGatewayStartupRecoveryAction({
+        startupError: new Error('Gateway process exited before becoming ready (code=1)'),
+        startupStderrLines: stderrLines,
+        configRepairAttempted: false,
+        attempt: 1,
+        maxAttempts: 3,
+      });
+      expect(action).toBe('fail');
+    });
+
+    it('getGatewayStartupRecoveryAction still retries transient errors without systemd signal', () => {
+      const action = getGatewayStartupRecoveryAction({
+        startupError: new Error('Gateway process exited before becoming ready (code=1)'),
+        startupStderrLines: [],
+        configRepairAttempted: false,
+        attempt: 1,
+        maxAttempts: 3,
+      });
+      expect(action).toBe('retry');
+    });
+  });
 });