diff --git a/src/uu/uniq/src/uniq.rs b/src/uu/uniq/src/uniq.rs
index 6037a66224..38f6b14694 100644
--- a/src/uu/uniq/src/uniq.rs
+++ b/src/uu/uniq/src/uniq.rs
@@ -723,7 +723,9 @@ pub fn uu_app() -> Command {
                 .value_name("delimit-method")
                 .num_args(0..=1)
                 .default_missing_value("none")
-                .require_equals(true),
+                .require_equals(true)
+                // GNU accepts a repeated -D/--all-repeated and uses the last one.
+                .overrides_with(options::ALL_REPEATED),
         )
         .arg(
             Arg::new(options::GROUP)
diff --git a/tests/by-util/test_uniq.rs b/tests/by-util/test_uniq.rs
index 8e940a743c..58a9bff062 100644
--- a/tests/by-util/test_uniq.rs
+++ b/tests/by-util/test_uniq.rs
@@ -162,6 +162,22 @@ fn test_stdin_all_repeated() {
         .stdout_is_fixture("sorted-all-repeated.expected");
 }
 
+#[test]
+fn test_all_repeated_repeated_last_wins() {
+    // GNU uniq accepts a repeated -D/--all-repeated and uses the last occurrence,
+    // instead of rejecting the second one.
+    new_ucmd!()
+        .args(&["-D", "--all-repeated=separate"])
+        .pipe_in("a\na\nb\nb\nc\n")
+        .succeeds()
+        .stdout_is("a\na\n\nb\nb\n");
+    new_ucmd!()
+        .args(&["-D", "-D"])
+        .pipe_in("a\na\n")
+        .succeeds()
+        .stdout_is("a\na\n");
+}
+
 #[test]
 fn test_all_repeated_followed_by_filename() {
     let filename = "test.txt";