diff --git a/Resources/shell-integration/.zshenv b/Resources/shell-integration/.zshenv
index 21570241..68925a2f 100644
--- a/Resources/shell-integration/.zshenv
+++ b/Resources/shell-integration/.zshenv
@@ -13,7 +13,9 @@
 # - CMUX_ZSH_ZDOTDIR (set by cmux when it overwrote a user-provided ZDOTDIR)
 # - unset (zsh treats unset ZDOTDIR as $HOME)
 
+builtin typeset _cmux_had_ghostty_zdotdir=0
 if [[ -n "${GHOSTTY_ZSH_ZDOTDIR+X}" ]]; then
+    _cmux_had_ghostty_zdotdir=1
     builtin export ZDOTDIR="$GHOSTTY_ZSH_ZDOTDIR"
     builtin unset GHOSTTY_ZSH_ZDOTDIR
 elif [[ -n "${CMUX_ZSH_ZDOTDIR+X}" ]]; then
@@ -31,7 +33,9 @@ fi
     if [[ -o interactive ]]; then
         # We overwrote GhosttyKit's injected ZDOTDIR, so manually load Ghostty's
         # zsh integration if available.
-        if [[ -n "${GHOSTTY_RESOURCES_DIR:-}" ]]; then
+        # Guard on GHOSTTY_ZSH_ZDOTDIR being set by Ghostty. When users configure
+        # shell-integration=none, Ghostty does not set this and we must skip.
+        if [[ "$_cmux_had_ghostty_zdotdir" == "1" && -n "${GHOSTTY_RESOURCES_DIR:-}" ]]; then
             builtin typeset _cmux_ghostty="$GHOSTTY_RESOURCES_DIR/shell-integration/zsh/ghostty-integration"
             [[ -r "$_cmux_ghostty" ]] && builtin source -- "$_cmux_ghostty"
         fi
@@ -43,5 +47,5 @@ fi
         fi
     fi
 
-    builtin unset _cmux_file _cmux_ghostty _cmux_integ
+    builtin unset _cmux_file _cmux_ghostty _cmux_integ _cmux_had_ghostty_zdotdir
 }
diff --git a/tests/test_issue_734_shell_integration_none_respected.py b/tests/test_issue_734_shell_integration_none_respected.py
new file mode 100644
index 00000000..3fe6836c
--- /dev/null
+++ b/tests/test_issue_734_shell_integration_none_respected.py
@@ -0,0 +1,132 @@
+#!/usr/bin/env python3
+"""
+Regression for issue #734:
+cmux wrapper .zshenv should only source Ghostty zsh integration when Ghostty
+actually enabled shell integration (signaled by GHOSTTY_ZSH_ZDOTDIR being set).
+"""
+
+from __future__ import annotations
+
+import os
+import shutil
+import subprocess
+from pathlib import Path
+
+
+def _run_case(
+    *,
+    wrapper_dir: Path,
+    home: Path,
+    orig_zdotdir: Path,
+    ghostty_resources: Path,
+    out_path: Path,
+    ghostty_enabled: bool,
+) -> tuple[int, str]:
+    env = dict(os.environ)
+    env["HOME"] = str(home)
+    env["ZDOTDIR"] = str(wrapper_dir)
+    env["GHOSTTY_RESOURCES_DIR"] = str(ghostty_resources)
+    env["CMUX_SHELL_INTEGRATION"] = "0"
+    env["CMUX_TEST_OUT"] = str(out_path)
+
+    # Keep input deterministic and local to this test.
+    for key in (
+        "GHOSTTY_ZSH_ZDOTDIR",
+        "CMUX_ZSH_ZDOTDIR",
+        "CMUX_ORIGINAL_ZDOTDIR",
+        "GHOSTTY_SHELL_FEATURES",
+        "GHOSTTY_BIN_DIR",
+    ):
+        env.pop(key, None)
+
+    if ghostty_enabled:
+        env["GHOSTTY_ZSH_ZDOTDIR"] = str(orig_zdotdir)
+    else:
+        env["CMUX_ZSH_ZDOTDIR"] = str(orig_zdotdir)
+
+    result = subprocess.run(
+        ["zsh", "-d", "-i", "-c", "true"],
+        env=env,
+        capture_output=True,
+        text=True,
+        timeout=8,
+    )
+    return (result.returncode, (result.stdout or "") + (result.stderr or ""))
+
+
+def main() -> int:
+    root = Path(__file__).resolve().parents[1]
+    wrapper_dir = root / "Resources" / "shell-integration"
+    if not (wrapper_dir / ".zshenv").exists():
+        print(f"SKIP: missing wrapper .zshenv at {wrapper_dir}")
+        return 0
+
+    base = Path("/tmp") / f"cmux_issue_734_{os.getpid()}"
+    try:
+        shutil.rmtree(base, ignore_errors=True)
+        base.mkdir(parents=True, exist_ok=True)
+
+        home = base / "home"
+        orig = base / "orig-zdotdir"
+        resources = base / "ghostty-resources"
+        home.mkdir(parents=True, exist_ok=True)
+        orig.mkdir(parents=True, exist_ok=True)
+        (resources / "shell-integration" / "zsh").mkdir(parents=True, exist_ok=True)
+
+        # Keep user startup files inert and local.
+        for filename in (".zshenv", ".zprofile", ".zshrc"):
+            (orig / filename).write_text("", encoding="utf-8")
+
+        marker = base / "ghostty-sourced.txt"
+        (resources / "shell-integration" / "zsh" / "ghostty-integration").write_text(
+            'echo "sourced" >> "$CMUX_TEST_OUT"\n',
+            encoding="utf-8",
+        )
+
+        rc, out = _run_case(
+            wrapper_dir=wrapper_dir,
+            home=home,
+            orig_zdotdir=orig,
+            ghostty_resources=resources,
+            out_path=marker,
+            ghostty_enabled=False,
+        )
+        if rc != 0:
+            print(f"FAIL: zsh exited non-zero when ghostty_enabled=False rc={rc}")
+            if out.strip():
+                print(out.strip())
+            return 1
+        if marker.exists():
+            print("FAIL: ghostty integration sourced when Ghostty shell integration was disabled")
+            return 1
+
+        rc, out = _run_case(
+            wrapper_dir=wrapper_dir,
+            home=home,
+            orig_zdotdir=orig,
+            ghostty_resources=resources,
+            out_path=marker,
+            ghostty_enabled=True,
+        )
+        if rc != 0:
+            print(f"FAIL: zsh exited non-zero when ghostty_enabled=True rc={rc}")
+            if out.strip():
+                print(out.strip())
+            return 1
+        if not marker.exists():
+            print("FAIL: ghostty integration not sourced when Ghostty shell integration was enabled")
+            return 1
+
+        contents = marker.read_text(encoding="utf-8")
+        if "sourced" not in contents:
+            print("FAIL: expected marker output missing after enabled run")
+            return 1
+
+        print("PASS: wrapper respects Ghostty shell-integration=none via GHOSTTY_ZSH_ZDOTDIR gate")
+        return 0
+    finally:
+        shutil.rmtree(base, ignore_errors=True)
+
+
+if __name__ == "__main__":
+    raise SystemExit(main())