diff --git a/src/uu/mktemp/src/mktemp.rs b/src/uu/mktemp/src/mktemp.rs
index 79810117643..64281e5756a 100644
--- a/src/uu/mktemp/src/mktemp.rs
+++ b/src/uu/mktemp/src/mktemp.rs
@@ -131,20 +131,22 @@ impl Options {
                 (tmpdir, OsString::from(template))
             }
             Some(template) => {
-                let tmpdir = if let Some(tmpdir) =
-                    env::var_os(TMPDIR_ENV_VAR).filter(|val| !val.is_empty())
+                let tmpdir = if let Some(tmpdir) = env::var_os(TMPDIR_ENV_VAR)
                     && matches.get_flag(OPT_T)
                 {
-                    // A non-empty `$TMPDIR` has priority over `-p` when
-                    // `-t` is given. An empty `$TMPDIR` is treated as
-                    // unset, so `-p` or the system default is used instead.
                     Some(PathBuf::from(tmpdir))
                 } else if tmpdir.is_some() {
                     tmpdir
                 } else if matches.get_flag(OPT_T) || matches.contains_id(OPT_TMPDIR) {
-                    // If --tmpdir is given without an argument, or -t is given,
-                    // export in TMPDIR.
-                    Some(get_tmpdir_env_or_default())
+                    // If --tmpdir is given without an argument, or -t is given
+                    // export in TMPDIR
+                    #[cfg(target_os = "wasi")]
+                    // WASI's `std::env::temp_dir()` unconditionally panics
+                    let default_tmp_dir = env::var_os(TMPDIR_ENV_VAR)
+                        .map_or_else(|| PathBuf::from(FALLBACK_TMPDIR), PathBuf::from);
+                    #[cfg(not(target_os = "wasi"))]
+                    let default_tmp_dir = env::temp_dir();
+                    Some(default_tmp_dir)
                 } else {
                     None
                 };
diff --git a/tests/by-util/test_mktemp.rs b/tests/by-util/test_mktemp.rs
index 72b3b640ffc..ca93e30b466 100644
--- a/tests/by-util/test_mktemp.rs
+++ b/tests/by-util/test_mktemp.rs
@@ -937,49 +937,6 @@ fn test_empty_tmpdir_env_var() {
     }
 }
 
-#[test]
-#[cfg_attr(wasi_runner, ignore = "WASI sandbox: host paths not visible")]
-fn test_empty_tmpdir_env_var_with_template() {
-    #[cfg(not(any(windows, target_os = "android")))]
-    {
-        let scene = TestScenario::new(util_name!());
-        let pathname = scene.fixtures.as_string();
-
-        // An empty `$TMPDIR` must be treated as unset, so `-t` and
-        // `--tmpdir` fall back to the system default temporary directory.
-        for args in [
-            vec!["-t", TEST_TEMPLATE1],
-            vec!["--tmpdir", TEST_TEMPLATE1],
-            vec!["-d", "-t", TEST_TEMPLATE1],
-        ] {
-            let result = scene.ucmd().env(TMPDIR, "").args(&args).succeeds();
-            let path = PathBuf::from(result.stdout_str().trim());
-            assert!(
-                path.starts_with("/tmp"),
-                "expected a path under /tmp, got {path:?}",
-            );
-            if path.is_dir() {
-                let _ = std::fs::remove_dir(&path);
-            } else {
-                let _ = std::fs::remove_file(&path);
-            }
-        }
-
-        // `-p` must take precedence over the empty `$TMPDIR`.
-        let result = scene
-            .ucmd()
-            .env(TMPDIR, "")
-            .args(&["-p", &pathname, "-t", TEST_TEMPLATE1])
-            .succeeds();
-        let path = PathBuf::from(result.stdout_str().trim());
-        assert!(
-            path.starts_with(&pathname),
-            "expected a path under {pathname}, got {path:?}",
-        );
-        let _ = std::fs::remove_file(&path);
-    }
-}
-
 #[test]
 fn test_nonexistent_dir_prefix() {
     #[cfg(not(windows))]