diff --git a/muxplex/cli.py b/muxplex/cli.py
index 4072063..f7476cb 100644
--- a/muxplex/cli.py
+++ b/muxplex/cli.py
@@ -342,6 +342,37 @@ def doctor() -> None:
         f" (auth={cfg['auth']}, ttl={cfg['session_ttl']}s)"
     )
 
+    # TLS status
+    tls_cert = cfg.get("tls_cert", "")
+    tls_key = cfg.get("tls_key", "")
+    if tls_cert and tls_key:
+        from datetime import datetime, timezone  # noqa: PLC0415
+
+        from muxplex.tls import get_cert_info  # noqa: PLC0415
+
+        cert_info = get_cert_info(tls_cert)
+        if cert_info is not None:
+            expires = cert_info["expires"]
+            # Ensure timezone-aware for comparison
+            if expires.tzinfo is None:
+                expires = expires.replace(tzinfo=timezone.utc)
+            now = datetime.now(timezone.utc)
+            if expires < now:
+                days_ago = (now - expires).days
+                print(
+                    f"  {warn_mark} TLS: WARNING \u2014 cert expired {days_ago} days ago."
+                    " Run muxplex setup-tls to renew"
+                )
+            else:
+                expiry_str = expires.strftime("%Y-%m-%d")
+                print(f"  {ok_mark} TLS: enabled (cert expires {expiry_str})")
+        else:
+            print(f"  {warn_mark} TLS: configured but cert not readable ({tls_cert})")
+    else:
+        print(
+            f"  {warn_mark} TLS: disabled (clipboard requires HTTPS on non-localhost)"
+        )
+
     # Auth status
     pw_path = get_password_path()
     if pam_available():
diff --git a/muxplex/tests/test_cli.py b/muxplex/tests/test_cli.py
index ee5f3cc..f189cf5 100644
--- a/muxplex/tests/test_cli.py
+++ b/muxplex/tests/test_cli.py
@@ -1561,3 +1561,76 @@ def test_serve_subcommand_accepts_tls_flags():
             tls_cert="/path/cert.pem",
             tls_key="/path/key.pem",
         )
+
+
+# ---------------------------------------------------------------------------
+# task-6-doctor-tls: TLS status section in doctor()
+# ---------------------------------------------------------------------------
+
+
+def test_doctor_shows_tls_disabled(tmp_path, monkeypatch, capsys):
+    """doctor() shows TLS disabled when no TLS configured."""
+    import muxplex.settings as settings_mod
+
+    settings_file = tmp_path / "settings.json"
+    # No tls_cert/tls_key — just use empty settings
+    settings_file.write_text("{}")
+    monkeypatch.setattr(settings_mod, "SETTINGS_PATH", settings_file)
+
+    from muxplex.cli import doctor
+
+    doctor()
+
+    out = capsys.readouterr().out
+    out_lower = out.lower()
+    assert "tls" in out_lower, f"Expected 'tls' in doctor output, got: {out!r}"
+    assert "disabled" in out_lower, (
+        f"Expected 'disabled' in doctor output, got: {out!r}"
+    )
+
+
+def test_doctor_shows_tls_enabled(tmp_path, monkeypatch, capsys):
+    """doctor() shows TLS enabled when valid certs are configured."""
+    import json
+
+    import muxplex.settings as settings_mod
+    from muxplex.tls import generate_self_signed
+
+    # Generate real self-signed certs in tmp_path
+    cert_path = tmp_path / "muxplex.crt"
+    key_path = tmp_path / "muxplex.key"
+    generate_self_signed(cert_path, key_path)
+
+    settings_file = tmp_path / "settings.json"
+    settings_file.write_text(
+        json.dumps({"tls_cert": str(cert_path), "tls_key": str(key_path)})
+    )
+    monkeypatch.setattr(settings_mod, "SETTINGS_PATH", settings_file)
+
+    from muxplex.cli import doctor
+
+    doctor()
+
+    out = capsys.readouterr().out
+    out_lower = out.lower()
+    assert "tls" in out_lower, f"Expected 'tls' in doctor output, got: {out!r}"
+    assert "enabled" in out_lower, f"Expected 'enabled' in doctor output, got: {out!r}"
+
+
+def test_doctor_shows_tls_clipboard_warning(tmp_path, monkeypatch, capsys):
+    """doctor() mentions clipboard or https when TLS is disabled."""
+    import muxplex.settings as settings_mod
+
+    settings_file = tmp_path / "settings.json"
+    settings_file.write_text("{}")
+    monkeypatch.setattr(settings_mod, "SETTINGS_PATH", settings_file)
+
+    from muxplex.cli import doctor
+
+    doctor()
+
+    out = capsys.readouterr().out
+    out_lower = out.lower()
+    assert "clipboard" in out_lower or "https" in out_lower, (
+        f"Expected 'clipboard' or 'https' in doctor TLS-disabled output, got: {out!r}"
+    )