diff --git a/noteguard.toml b/noteguard.toml
index 467693c..7b13cd8 100644
--- a/noteguard.toml
+++ b/noteguard.toml
@@ -1,4 +1,3 @@
-
 pipeline = ["protected_events", "kinds", "content", "whitelist", "ratelimit"]
 
 [filters.ratelimit]
diff --git a/src/filters/blacklist.rs b/src/filters/blacklist.rs
new file mode 100644
index 0000000..e72fb2e
--- /dev/null
+++ b/src/filters/blacklist.rs
@@ -0,0 +1,39 @@
+use crate::{Action, InputMessage, NoteFilter, OutputMessage};
+use serde::Deserialize;
+
+#[derive(Deserialize, Default)]
+pub struct Blacklist {
+    pub pubkeys: Option<Vec<String>>,
+    pub ips: Option<Vec<String>>,
+}
+
+impl NoteFilter for Blacklist {
+    fn filter_note(&mut self, msg: &InputMessage) -> OutputMessage {
+        let reject_message = "blocked: pubkey/ip is blacklisted".to_string();
+        if let Some(pubkeys) = &self.pubkeys {
+            if pubkeys.contains(&msg.event.pubkey) {
+                return OutputMessage::new(
+                    msg.event.id.clone(),
+                    Action::Reject,
+                    Some(reject_message),
+                );
+            }
+        }
+
+        if let Some(ips) = &self.ips {
+            if ips.contains(&msg.source_info) {
+                return OutputMessage::new(
+                    msg.event.id.clone(),
+                    Action::Reject,
+                    Some(reject_message),
+                );
+            }
+        }
+
+        OutputMessage::new(msg.event.id.clone(), Action::Accept, None)
+    }
+
+    fn name(&self) -> &'static str {
+        "blacklist"
+    }
+}
diff --git a/src/filters/mod.rs b/src/filters/mod.rs
index 0fa5611..da41573 100644
--- a/src/filters/mod.rs
+++ b/src/filters/mod.rs
@@ -1,3 +1,4 @@
+mod blacklist;
 mod content;
 mod kinds;
 mod protected_events;
@@ -7,6 +8,7 @@ mod whitelist;
 #[cfg(feature = "forwarder")]
 mod forwarder;
 
+pub use blacklist::Blacklist;
 pub use content::Content;
 pub use kinds::Kinds;
 pub use protected_events::ProtectedEvents;
diff --git a/src/main.rs b/src/main.rs
index 19cb307..16b1d2d 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -1,4 +1,4 @@
-use noteguard::filters::{Content, Kinds, ProtectedEvents, RateLimit, Whitelist};
+use noteguard::filters::{Blacklist, Content, Kinds, ProtectedEvents, RateLimit, Whitelist};
 
 #[cfg(feature = "forwarder")]
 use noteguard::filters::Forwarder;
@@ -47,6 +47,7 @@ impl Noteguard {
     fn register_builtin_filters(&mut self) {
         self.register_filter::<RateLimit>();
         self.register_filter::<Whitelist>();
+        self.register_filter::<Blacklist>();
         self.register_filter::<ProtectedEvents>();
         self.register_filter::<Kinds>();
         self.register_filter::<Content>();
@@ -217,6 +218,7 @@ mod tests {
         let noteguard = Noteguard::new();
         assert!(noteguard.registered_filters.contains_key("ratelimit"));
         assert!(noteguard.registered_filters.contains_key("whitelist"));
+        assert!(noteguard.registered_filters.contains_key("blacklist"));
         assert!(noteguard
             .registered_filters
             .contains_key("protected_events"));
@@ -315,6 +317,56 @@ mod tests {
         assert_eq!(output_message.action, Action::Reject);
     }
 
+    #[test]
+    fn test_blacklist_reject() {
+        let mut noteguard = Noteguard::new();
+
+        let config: Config = toml::from_str(
+            r#"
+            pipeline = ["blacklist"]
+            [filters.blacklist]
+            pubkeys = ["mock_pubkey"]
+        "#,
+        )
+        .expect("Failed to parse config");
+
+        noteguard
+            .load_config(&config)
+            .expect("Failed to load config");
+
+        let input_message = create_mock_input_message("test_event_3", "new");
+        let output_message = noteguard.run(input_message);
+
+        assert_eq!(output_message.action, Action::Reject);
+        assert_eq!(
+            output_message.msg.expect("Failed to get message"),
+            "blocked: pubkey/ip is blacklisted".to_string()
+        );
+    }
+
+    #[test]
+    fn test_blacklist_accept() {
+        let mut noteguard = Noteguard::new();
+
+        let config: Config = toml::from_str(
+            r#"
+            pipeline = ["blacklist"]
+            [filters.blacklist]
+            pubkeys = ["not_blacklisted"]
+        "#,
+        )
+        .expect("Failed to parse config");
+
+        noteguard
+            .load_config(&config)
+            .expect("Failed to load config");
+
+        let input_message = create_mock_input_message("test_event_4", "new");
+        let output_message = noteguard.run(input_message);
+
+        assert_eq!(output_message.action, Action::Accept);
+    }
+
     #[test]
     fn test_deserialize_input_message() {
         let input_json = r#"