diff --git a/crates/backend/src/ast.rs b/crates/backend/src/ast.rs
index 7d5c1e0c..cbacc189 100644
--- a/crates/backend/src/ast.rs
+++ b/crates/backend/src/ast.rs
@@ -16,6 +16,8 @@ pub struct NapiFn {
   pub parent: Option<Ident>,
   pub strict: bool,
   pub js_mod: Option<String>,
+  pub ts_args_type: Option<String>,
+  pub ts_return_type: Option<String>,
 }
 
 #[derive(Debug, Clone)]
diff --git a/crates/backend/src/typegen.rs b/crates/backend/src/typegen.rs
index 1d7ca257..60ef40fc 100644
--- a/crates/backend/src/typegen.rs
+++ b/crates/backend/src/typegen.rs
@@ -67,6 +67,7 @@ static KNOWN_TYPES: Lazy<HashMap<&'static str, &'static str>> = Lazy::new(|| {
     ("char", "string"),
     ("JsObject", "object"),
     ("Object", "object"),
+    ("Array", "unknown[]"),
     ("Value", "any"),
     ("Map", "Record<string, any>"),
     ("HashMap", "Record<{}, {}>"),
diff --git a/crates/backend/src/typegen/fn.rs b/crates/backend/src/typegen/fn.rs
index 6f2ed754..24e0cc82 100644
--- a/crates/backend/src/typegen/fn.rs
+++ b/crates/backend/src/typegen/fn.rs
@@ -11,8 +11,15 @@ impl ToTypeDef for NapiFn {
       r#"{prefix} {name}({args}){ret}"#,
       prefix = self.gen_ts_func_prefix(),
       name = &self.js_name,
-      args = self.gen_ts_func_args(),
-      ret = self.gen_ts_func_ret(),
+      args = self
+        .ts_args_type
+        .clone()
+        .unwrap_or_else(|| self.gen_ts_func_args()),
+      ret = self
+        .ts_return_type
+        .clone()
+        .map(|t| format!(": {}", t))
+        .unwrap_or_else(|| self.gen_ts_func_ret()),
     );
 
     TypeDef {
diff --git a/crates/macro/src/parser/attrs.rs b/crates/macro/src/parser/attrs.rs
index a53e8272..a04da0ef 100644
--- a/crates/macro/src/parser/attrs.rs
+++ b/crates/macro/src/parser/attrs.rs
@@ -53,12 +53,13 @@ macro_rules! attrgen {
       (strict, Strict(Span)),
       (object, Object(Span)),
       (namespace, Namespace(Span, String, Span)),
+      (ts_args_type, TsArgsType(Span, String, Span)),
+      (ts_return_type, TsReturnType(Span, String, Span)),
 
       // impl later
       // (inspectable, Inspectable(Span)),
       // (typescript_custom_section, TypescriptCustomSection(Span)),
       // (skip_typescript, SkipTypescript(Span)),
-      // (typescript_type, TypeScriptType(Span, String, Span)),
       // (getter_with_clone, GetterWithClone(Span)),
 
       // For testing purposes only.
diff --git a/crates/macro/src/parser/mod.rs b/crates/macro/src/parser/mod.rs
index 9d6a2b65..fa0b109b 100644
--- a/crates/macro/src/parser/mod.rs
+++ b/crates/macro/src/parser/mod.rs
@@ -575,6 +575,8 @@ fn napi_fn_from_decl(
       attrs,
       strict: opts.strict().is_some(),
       js_mod: opts.namespace().map(|(m, _)| m.to_owned()),
+      ts_args_type: opts.ts_args_type().map(|(m, _)| m.to_owned()),
+      ts_return_type: opts.ts_return_type().map(|(m, _)| m.to_owned()),
     }
   })
 }
@@ -603,6 +605,12 @@ impl ParseNapi for syn::ItemFn {
 }
 impl ParseNapi for syn::ItemStruct {
   fn parse_napi(&mut self, tokens: &mut TokenStream, opts: BindgenAttrs) -> BindgenResult<Napi> {
+    if opts.ts_args_type().is_some() || opts.ts_return_type().is_some() {
+      bail_span!(
+        self,
+        "#[napi] can't be applied to a struct with #[napi(ts_args_type)] or #[napi(ts_return_type)]"
+      );
+    }
     let napi = self.convert_to_ast(opts);
     self.to_tokens(tokens);
 
@@ -611,6 +619,12 @@ impl ParseNapi for syn::ItemStruct {
 }
 impl ParseNapi for syn::ItemImpl {
   fn parse_napi(&mut self, tokens: &mut TokenStream, opts: BindgenAttrs) -> BindgenResult<Napi> {
+    if opts.ts_args_type().is_some() || opts.ts_return_type().is_some() {
+      bail_span!(
+        self,
+        "#[napi] can't be applied to impl with #[napi(ts_args_type)] or #[napi(ts_return_type)]"
+      );
+    }
     // #[napi] macro will be remove from impl items after converted to ast
     let napi = self.convert_to_ast(opts);
     self.to_tokens(tokens);
@@ -618,18 +632,28 @@ impl ParseNapi for syn::ItemImpl {
     napi
   }
 }
-
 impl ParseNapi for syn::ItemEnum {
   fn parse_napi(&mut self, tokens: &mut TokenStream, opts: BindgenAttrs) -> BindgenResult<Napi> {
+    if opts.ts_args_type().is_some() || opts.ts_return_type().is_some() {
+      bail_span!(
+        self,
+        "#[napi] can't be applied to a enum with #[napi(ts_args_type)] or #[napi(ts_return_type)]"
+      );
+    }
     let napi = self.convert_to_ast(opts);
     self.to_tokens(tokens);
 
     napi
   }
 }
-
 impl ParseNapi for syn::ItemConst {
   fn parse_napi(&mut self, tokens: &mut TokenStream, opts: BindgenAttrs) -> BindgenResult<Napi> {
+    if opts.ts_args_type().is_some() || opts.ts_return_type().is_some() {
+      bail_span!(
+        self,
+        "#[napi] can't be applied to a const with #[napi(ts_args_type)] or #[napi(ts_return_type)]"
+      );
+    }
     let napi = self.convert_to_ast(opts);
     self.to_tokens(tokens);
     napi
diff --git a/examples/napi/__test__/typegen.spec.ts.md b/examples/napi/__test__/typegen.spec.ts.md
index 31303f56..d2d2f385 100644
--- a/examples/napi/__test__/typegen.spec.ts.md
+++ b/examples/napi/__test__/typegen.spec.ts.md
@@ -42,6 +42,7 @@ Generated by [AVA](https://avajs.dev).
     export function createExternalString(content: string): ExternalObject<string>␊
     export function getExternal(external: ExternalObject<number>): number␊
     export function mutateExternal(external: ExternalObject<number>, newVal: number): void␊
+    export function tsRename(a: { foo: number }): string[]␊
     export function xxh64Alias(input: Buffer): BigInt␊
     export function mapOption(val?: number | undefined | null): number | undefined | null␊
     export function add(a: number, b: number): number␊
diff --git a/examples/napi/__test__/typegen.spec.ts.snap b/examples/napi/__test__/typegen.spec.ts.snap
index 1357fa79..ac8bd40a 100644
Binary files a/examples/napi/__test__/typegen.spec.ts.snap and b/examples/napi/__test__/typegen.spec.ts.snap differ
diff --git a/examples/napi/__test__/values.spec.ts b/examples/napi/__test__/values.spec.ts
index ecd626a0..01c83b59 100644
--- a/examples/napi/__test__/values.spec.ts
+++ b/examples/napi/__test__/values.spec.ts
@@ -55,6 +55,7 @@ import {
   xxh2,
   xxh3,
   xxh64Alias,
+  tsRename,
 } from '../'
 
 test('export const', (t) => {
@@ -194,6 +195,10 @@ test('Result', (t) => {
   t.throws(() => throwError(), null, 'Manual Error')
 })
 
+test('function ts type override', (t) => {
+  t.deepEqual(tsRename({ foo: 1, bar: 2, baz: 2 }), ['foo', 'bar', 'baz'])
+})
+
 test('serde-json', (t) => {
   const packageJson = readPackageJson()
   t.is(packageJson.name, 'napi-rs')
diff --git a/examples/napi/index.d.ts b/examples/napi/index.d.ts
index d9afc5fd..40eadb14 100644
--- a/examples/napi/index.d.ts
+++ b/examples/napi/index.d.ts
@@ -32,6 +32,7 @@ export function createExternal(size: number): ExternalObject<number>
 export function createExternalString(content: string): ExternalObject<string>
 export function getExternal(external: ExternalObject<number>): number
 export function mutateExternal(external: ExternalObject<number>, newVal: number): void
+export function tsRename(a: { foo: number }): string[]
 export function xxh64Alias(input: Buffer): BigInt
 export function mapOption(val?: number | undefined | null): number | undefined | null
 export function add(a: number, b: number): number
diff --git a/examples/napi/src/fn_ts_override.rs b/examples/napi/src/fn_ts_override.rs
new file mode 100644
index 00000000..7793325f
--- /dev/null
+++ b/examples/napi/src/fn_ts_override.rs
@@ -0,0 +1,6 @@
+use napi::bindgen_prelude::{Object, Result};
+
+#[napi(ts_args_type = "a: { foo: number }", ts_return_type = "string[]")]
+fn ts_rename(a: Object) -> Result<Object> {
+  a.get_property_names()
+}
diff --git a/examples/napi/src/lib.rs b/examples/napi/src/lib.rs
index 751d16c9..9cf239a1 100644
--- a/examples/napi/src/lib.rs
+++ b/examples/napi/src/lib.rs
@@ -16,6 +16,7 @@ mod either;
 mod r#enum;
 mod error;
 mod external;
+mod fn_ts_override;
 mod js_mod;
 mod nullable;
 mod number;