diff --git a/src/rest-client-v5.ts b/src/rest-client-v5.ts
index 9653caa..14f12c7 100644
--- a/src/rest-client-v5.ts
+++ b/src/rest-client-v5.ts
@@ -231,9 +231,9 @@ export class RestClientV5 extends BaseRestClient {
    *
    * Note: Spot does not support pagination, so limit & cursor are invalid.
    */
-  getInstrumentsInfo(
-    params: GetInstrumentsInfoParamsV5,
-  ): Promise<APIResponseV3WithTime<InstrumentInfoResponseV5>> {
+  getInstrumentsInfo<C extends CategoryV5>(
+    params: GetInstrumentsInfoParamsV5 & { category: C },
+  ): Promise<APIResponseV3WithTime<InstrumentInfoResponseV5<C>>> {
     return this.get('/v5/market/instruments-info', params);
   }
 
diff --git a/src/types/response/v5-market.ts b/src/types/response/v5-market.ts
index d65a1f7..9025e12 100644
--- a/src/types/response/v5-market.ts
+++ b/src/types/response/v5-market.ts
@@ -1,5 +1,6 @@
 import {
   CategoryCursorListV5,
+  CategoryV5,
   ContractTypeV5,
   InstrumentStatusV5,
   OptionTypeV5,
@@ -110,10 +111,14 @@ export interface SpotInstrumentInfoV5 {
   };
 }
 
-export type InstrumentInfoResponseV5 =
-  | CategoryCursorListV5<LinearInverseInstrumentInfoV5[], 'linear' | 'inverse'>
-  | CategoryCursorListV5<OptionInstrumentInfoV5[], 'option'>
-  | CategoryCursorListV5<SpotInstrumentInfoV5[], 'spot'>;
+type InstrumentInfoV5Mapping = {
+  linear: LinearInverseInstrumentInfoV5[],
+  inverse: LinearInverseInstrumentInfoV5[],
+  option: OptionInstrumentInfoV5[],
+  spot: SpotInstrumentInfoV5[]
+};
+
+export type InstrumentInfoResponseV5<C extends CategoryV5> = CategoryCursorListV5<InstrumentInfoV5Mapping[C], C>;
 
 export default interface OrderbookLevelV5 {
   price: string;