diff --git a/tests/by-util/test_mcookie.rs b/tests/by-util/test_mcookie.rs
new file mode 100644
index 0000000..9167b80
--- /dev/null
+++ b/tests/by-util/test_mcookie.rs
@@ -0,0 +1,65 @@
+// This file is part of the uutils util-linux package.
+//
+// For the full copyright and license information, please view the LICENSE
+// file that was distributed with this source code.
+
+use std::io::Write;
+
+use tempfile::{NamedTempFile, TempDir};
+
+use crate::common::util::TestScenario;
+
+#[test]
+fn test_invalid_arg() {
+    new_ucmd!().arg("--definitely-invalid").fails().code_is(1);
+}
+
+#[test]
+fn test_basic_usage() {
+    let res = new_ucmd!().succeeds();
+
+    let stdout = res.no_stderr().stdout_str();
+
+    // Expect 32 hex characters for the MD5 hash (after trimming the newline)
+    assert_eq!(stdout.trim_end().len(), 32);
+    assert!(stdout.trim_end().chars().all(|c| c.is_ascii_hexdigit()));
+}
+
+#[test]
+fn test_verbose() {
+    let res = new_ucmd!().arg("--verbose").succeeds();
+    res.stderr_contains("Got 128 bytes from randomness source");
+}
+
+#[test]
+fn test_seed_files_and_max_size() {
+    let mut file1 = NamedTempFile::new().unwrap();
+    const CONTENT1: &str = "Some seed data";
+    file1.write_all(CONTENT1.as_bytes()).unwrap();
+
+    let mut file2 = NamedTempFile::new().unwrap();
+    const CONTENT2: [u8; 2048] = [1; 2048];
+    file2.write_all(&CONTENT2).unwrap();
+
+    let res = new_ucmd!()
+        .arg("--verbose")
+        .arg("-f")
+        .arg(file1.path())
+        .arg("-f")
+        .arg(file2.path())
+        .arg("-m")
+        .arg("1337")
+        .succeeds();
+
+    res.stderr_contains(format!(
+        "Got {} bytes from {}",
+        CONTENT1.len(),
+        file1.path().to_str().unwrap()
+    ));
+
+    // Ensure we only read up to the limit of bytes, despite the file being bigger
+    res.stderr_contains(format!(
+        "Got 1337 bytes from {}",
+        file2.path().to_str().unwrap()
+    ));
+}
diff --git a/tests/tests.rs b/tests/tests.rs
index c2054a5..0fb3ed1 100644
--- a/tests/tests.rs
+++ b/tests/tests.rs
@@ -56,3 +56,7 @@ mod test_dmesg;
 #[cfg(feature = "fsfreeze")]
 #[path = "by-util/test_fsfreeze.rs"]
 mod test_fsfreeze;
+
+#[cfg(feature = "mcookie")]
+#[path = "by-util/test_mcookie.rs"]
+mod test_mcookie;