diff --git a/scripts/e2e/lib/plugins/clawhub.sh b/scripts/e2e/lib/plugins/clawhub.sh
index 6248ca2739a6..846c424bac21 100644
--- a/scripts/e2e/lib/plugins/clawhub.sh
+++ b/scripts/e2e/lib/plugins/clawhub.sh
@@ -16,11 +16,11 @@ run_plugins_clawhub_scenario() {
       node scripts/e2e/lib/clawhub-fixture-server.cjs plugins "$server_port_file" >"$server_log" 2>&1 &
       local server_pid="$!"
       echo "$server_pid" >"$server_pid_file"
+      openclaw_plugins_register_fixture_pid_file "$server_pid_file"
 
       for _ in $(seq 1 100); do
         if [[ -s "$server_port_file" ]]; then
           export OPENCLAW_CLAWHUB_URL="http://127.0.0.1:$(cat "$server_port_file")"
-          openclaw_plugins_register_fixture_pid_file "$server_pid_file"
           return 0
         fi
         if ! kill -0 "$server_pid" 2>/dev/null; then
diff --git a/scripts/e2e/lib/plugins/fixtures.sh b/scripts/e2e/lib/plugins/fixtures.sh
index 3ac506fd82f9..e9a88ee450c5 100644
--- a/scripts/e2e/lib/plugins/fixtures.sh
+++ b/scripts/e2e/lib/plugins/fixtures.sh
@@ -1,4 +1,6 @@
 OPENCLAW_PLUGINS_FIXTURE_PID_FILES=()
+OPENCLAW_PLUGINS_FIXTURE_EXIT_TRAP_INSTALLED=0
+OPENCLAW_PLUGINS_FIXTURE_PREVIOUS_EXIT_ACTION=""
 
 openclaw_plugins_cleanup_fixture_servers() {
   local pid_file
@@ -16,7 +18,33 @@ openclaw_plugins_cleanup_fixture_servers() {
 openclaw_plugins_register_fixture_pid_file() {
   local pid_file="$1"
   OPENCLAW_PLUGINS_FIXTURE_PID_FILES+=("$pid_file")
-  trap openclaw_plugins_cleanup_fixture_servers EXIT
+  openclaw_plugins_install_fixture_cleanup_trap
+}
+
+openclaw_plugins_install_fixture_cleanup_trap() {
+  if [[ "${OPENCLAW_PLUGINS_FIXTURE_EXIT_TRAP_INSTALLED:-0}" = "1" ]]; then
+    return
+  fi
+
+  local existing_trap
+  existing_trap="$(trap -p EXIT || true)"
+  if [[ -n "$existing_trap" && "$existing_trap" != *openclaw_plugins_fixture_exit_trap* ]]; then
+    local existing_action="${existing_trap#trap -- }"
+    existing_action="${existing_action% EXIT}"
+    eval "OPENCLAW_PLUGINS_FIXTURE_PREVIOUS_EXIT_ACTION=$existing_action"
+  fi
+
+  OPENCLAW_PLUGINS_FIXTURE_EXIT_TRAP_INSTALLED=1
+  trap openclaw_plugins_fixture_exit_trap EXIT
+}
+
+openclaw_plugins_fixture_exit_trap() {
+  local status="$?"
+  openclaw_plugins_cleanup_fixture_servers
+  if [[ -n "${OPENCLAW_PLUGINS_FIXTURE_PREVIOUS_EXIT_ACTION:-}" ]]; then
+    eval "$OPENCLAW_PLUGINS_FIXTURE_PREVIOUS_EXIT_ACTION"
+  fi
+  exit "$status"
 }
 
 record_fixture_plugin_trust() {
@@ -142,11 +170,11 @@ start_npm_fixture_registry() {
   node scripts/e2e/lib/plugins/npm-registry-server.mjs "$server_port_file" "$package_name" "$version" "$tarball" "$@" >"$server_log" 2>&1 &
   local server_pid="$!"
   echo "$server_pid" >"$server_pid_file"
+  openclaw_plugins_register_fixture_pid_file "$server_pid_file"
 
   for _ in $(seq 1 100); do
     if [[ -s "$server_port_file" ]]; then
       export NPM_CONFIG_REGISTRY="http://127.0.0.1:$(cat "$server_port_file")"
-      openclaw_plugins_register_fixture_pid_file "$server_pid_file"
       return 0
     fi
     if ! kill -0 "$server_pid" 2>/dev/null; then
diff --git a/test/scripts/plugins-assertions.test.ts b/test/scripts/plugins-assertions.test.ts
index b3506b655461..f81535444266 100644
--- a/test/scripts/plugins-assertions.test.ts
+++ b/test/scripts/plugins-assertions.test.ts
@@ -1,5 +1,5 @@
 import { spawn, spawnSync } from "node:child_process";
-import { mkdirSync, mkdtempSync, readFileSync, rmSync, writeFileSync } from "node:fs";
+import { chmodSync, mkdirSync, mkdtempSync, readFileSync, rmSync, writeFileSync } from "node:fs";
 import { createServer } from "node:http";
 import { tmpdir } from "node:os";
 import path from "node:path";
@@ -7,6 +7,10 @@ import { describe, expect, it } from "vitest";
 
 const ASSERTIONS_SCRIPT = "scripts/e2e/lib/plugins/assertions.mjs";
 
+function shellQuote(value: string): string {
+  return `'${value.replace(/'/gu, `'\\''`)}'`;
+}
+
 function writeJson(filePath: string, value: unknown) {
   mkdirSync(path.dirname(filePath), { recursive: true });
   writeFileSync(filePath, `${JSON.stringify(value, null, 2)}\n`, "utf8");
@@ -47,6 +51,43 @@ function runAssertionAsync(args: string[], env: NodeJS.ProcessEnv) {
   );
 }
 
+function writeFixtureServerShims(binDir: string, pidPath: string): void {
+  mkdirSync(binDir, { recursive: true });
+  writeFileSync(
+    path.join(binDir, "node"),
+    [
+      "#!/bin/bash",
+      'printf "%s\\n" "$$" >"$OPENCLAW_TEST_FIXTURE_SERVER_PID"',
+      "trap 'exit 0' TERM",
+      "while true; do /bin/sleep 1; done",
+      "",
+    ].join("\n"),
+  );
+  writeFileSync(path.join(binDir, "sleep"), "#!/bin/bash\nexit 0\n");
+  chmodSync(path.join(binDir, "node"), 0o755);
+  chmodSync(path.join(binDir, "sleep"), 0o755);
+  writeFileSync(pidPath, "");
+}
+
+function isProcessAlive(pid: number): boolean {
+  try {
+    process.kill(pid, 0);
+    return true;
+  } catch {
+    return false;
+  }
+}
+
+function waitForDead(pid: number, timeoutMs = 2_000): void {
+  const startedAt = Date.now();
+  while (isProcessAlive(pid)) {
+    if (Date.now() - startedAt > timeoutMs) {
+      throw new Error(`pid ${pid} is still alive`);
+    }
+    Atomics.wait(new Int32Array(new SharedArrayBuffer(4)), 0, 0, 20);
+  }
+}
+
 describe("plugins Docker assertions", () => {
   it("rejects loose ClawHub preflight limits instead of parsing prefixes", () => {
     const timeoutResult = spawnSync(process.execPath, [ASSERTIONS_SCRIPT, "clawhub-preflight"], {
@@ -92,6 +133,99 @@ describe("plugins Docker assertions", () => {
     }
   });
 
+  it("cleans npm fixture registry children when readiness times out", () => {
+    const root = mkdtempSync(path.join(tmpdir(), "openclaw-plugin-npm-fixture-cleanup-"));
+    try {
+      const binDir = path.join(root, "bin");
+      const fixtureDir = path.join(root, "fixture");
+      const cleanupPath = path.join(root, "caller-cleanup");
+      const pidPath = path.join(root, "server.pid");
+      mkdirSync(fixtureDir);
+      writeFixtureServerShims(binDir, pidPath);
+
+      const result = spawnSync(
+        "/bin/bash",
+        [
+          "-c",
+          [
+            "set -euo pipefail",
+            "source scripts/e2e/lib/plugins/fixtures.sh",
+            "set +e",
+            `( set -e; trap 'printf caller-cleanup > ${shellQuote(cleanupPath)}' EXIT; start_npm_fixture_registry fixture-pkg 1.0.0 ${shellQuote(path.join(root, "fixture.tgz"))} ${shellQuote(fixtureDir)} )`,
+            'status="$?"',
+            "set -e",
+            '[ "$status" != "0" ]',
+          ].join("\n"),
+        ],
+        {
+          cwd: process.cwd(),
+          encoding: "utf8",
+          env: {
+            ...process.env,
+            OPENCLAW_TEST_FIXTURE_SERVER_PID: pidPath,
+            PATH: `${binDir}${path.delimiter}/usr/bin${path.delimiter}/bin`,
+          },
+        },
+      );
+
+      expect(result.status, result.stderr || result.stdout).toBe(0);
+      const pid = Number(readFileSync(pidPath, "utf8"));
+      expect(Number.isInteger(pid)).toBe(true);
+      waitForDead(pid);
+      expect(readFileSync(cleanupPath, "utf8")).toBe("caller-cleanup");
+    } finally {
+      rmSync(root, { force: true, recursive: true });
+    }
+  });
+
+  it("cleans ClawHub fixture children when readiness times out", () => {
+    const root = mkdtempSync(path.join(tmpdir(), "openclaw-plugin-clawhub-fixture-cleanup-"));
+    try {
+      const binDir = path.join(root, "bin");
+      const cleanupPath = path.join(root, "caller-cleanup");
+      const tmpDir = path.join(root, "scratch");
+      const pidPath = path.join(root, "server.pid");
+      mkdirSync(tmpDir);
+      writeFixtureServerShims(binDir, pidPath);
+
+      const result = spawnSync(
+        "/bin/bash",
+        [
+          "-c",
+          [
+            "set -euo pipefail",
+            "source scripts/e2e/lib/plugins/fixtures.sh",
+            "source scripts/e2e/lib/plugins/clawhub.sh",
+            "set +e",
+            `( set -e; trap 'printf caller-cleanup > ${shellQuote(cleanupPath)}' EXIT; run_plugins_clawhub_scenario )`,
+            'status="$?"',
+            "set -e",
+            '[ "$status" != "0" ]',
+          ].join("\n"),
+        ],
+        {
+          cwd: process.cwd(),
+          encoding: "utf8",
+          env: {
+            ...process.env,
+            OPENCLAW_PLUGINS_E2E_LIVE_CLAWHUB: "0",
+            OPENCLAW_PLUGINS_TMP_DIR: tmpDir,
+            OPENCLAW_TEST_FIXTURE_SERVER_PID: pidPath,
+            PATH: `${binDir}${path.delimiter}/usr/bin${path.delimiter}/bin`,
+          },
+        },
+      );
+
+      expect(result.status, result.stderr || result.stdout).toBe(0);
+      const pid = Number(readFileSync(pidPath, "utf8"));
+      expect(Number.isInteger(pid)).toBe(true);
+      waitForDead(pid);
+      expect(readFileSync(cleanupPath, "utf8")).toBe("caller-cleanup");
+    } finally {
+      rmSync(root, { force: true, recursive: true });
+    }
+  });
+
   it("uses the configured scratch root and resolves Windows home-relative install paths", () => {
     const root = mkdtempSync(path.join(tmpdir(), "openclaw-plugins-assertions-"));
     const home = path.join(root, "home");