diff --git a/src/uu/pidof/src/pidof.rs b/src/uu/pidof/src/pidof.rs
index 00069481..e47563ff 100644
--- a/src/uu/pidof/src/pidof.rs
+++ b/src/uu/pidof/src/pidof.rs
@@ -185,7 +185,7 @@ pub fn uu_app() -> Command {
                 .help("Omit results with a given PID")
                 .value_delimiter(',')
                 .action(ArgAction::Append)
-                .value_parser(clap::value_parser!(usize))
+                .value_parser(parse_omit_pid)
                 .value_name("PID"),
         )
         .arg(
@@ -222,3 +222,13 @@ pub fn uu_app() -> Command {
                 .action(ArgAction::SetTrue),
         )
 }
+
+/// Parse an `-o` value: a PID, or `%PPID` for the parent of pidof (the
+/// calling shell or script).
+fn parse_omit_pid(value: &str) -> Result<usize, String> {
+    #[cfg(unix)]
+    if value == "%PPID" {
+        return Ok(std::os::unix::process::parent_id() as usize);
+    }
+    value.parse::<usize>().map_err(|e| e.to_string())
+}
diff --git a/tests/by-util/test_pidof.rs b/tests/by-util/test_pidof.rs
index 3dc7059d..f48cc0b0 100644
--- a/tests/by-util/test_pidof.rs
+++ b/tests/by-util/test_pidof.rs
@@ -83,6 +83,32 @@ fn test_omit_pid() {
     }
 }
 
+#[test]
+#[cfg(target_os = "linux")]
+fn test_omit_pid_ppid() {
+    // pidof runs as a child of this test, so %PPID names this process.
+    let exe = std::env::current_exe().unwrap();
+    let our_name = exe.file_name().unwrap().to_str().unwrap();
+    let our_pid = std::process::id().to_string();
+
+    new_ucmd!()
+        .arg(our_name)
+        .succeeds()
+        .stdout_contains(&our_pid);
+    for omit in ["%PPID", "1,%PPID"] {
+        let result = new_ucmd!().args(&["-o", omit, our_name]).run();
+        result.no_stderr();
+        assert!(
+            !result
+                .stdout_str()
+                .split_whitespace()
+                .any(|pid| pid == our_pid),
+            "-o {omit}: {} contains {our_pid}",
+            result.stdout_str()
+        );
+    }
+}
+
 #[test]
 #[cfg(target_os = "linux")]
 fn test_separator() {