diff --git a/packages/api/src/beacon/routes/beacon/block.ts b/packages/api/src/beacon/routes/beacon/block.ts
index 95a32097028d..c1f1e723e358 100644
--- a/packages/api/src/beacon/routes/beacon/block.ts
+++ b/packages/api/src/beacon/routes/beacon/block.ts
@@ -229,8 +229,12 @@ export type Api = {
    * Retrieves BlobSidecar included in requested block.
    * @param blockId Block identifier.
    * Can be one of: "head" (canonical head in node's view), "genesis", "finalized", \<slot\>, \<hex encoded blockRoot with 0x prefix\>.
+   * @param indices Array of indices for blob sidecars to request for in the specified block. Returns all blob sidecars in the block if not specified.
    */
-  getBlobSidecars(blockId: BlockId): Promise<
+  getBlobSidecars(
+    blockId: BlockId,
+    indices?: number[]
+  ): Promise<
     ApiClientResponse<{
       [HttpStatusCode.OK]: {executionOptimistic: ExecutionOptimistic; data: deneb.BlobSidecars};
     }>
@@ -270,7 +274,7 @@ export type ReqTypes = {
   publishBlockV2: {body: unknown; query: {broadcast_validation?: string}};
   publishBlindedBlock: {body: unknown};
   publishBlindedBlockV2: {body: unknown; query: {broadcast_validation?: string}};
-  getBlobSidecars: BlockIdOnlyReq;
+  getBlobSidecars: {params: {block_id: string}; query: {indices?: number[]}};
 };
 
 export function getReqSerializers(config: ChainForkConfig): ReqSerializers<Api, ReqTypes> {
@@ -356,7 +360,16 @@ export function getReqSerializers(config: ChainForkConfig): ReqSerializers<Api,
         query: {broadcast_validation: Schema.String},
       },
     },
-    getBlobSidecars: blockIdOnlyReq,
+    getBlobSidecars: {
+      writeReq: (block_id, indices) => ({
+        params: {block_id: String(block_id)},
+        query: {indices},
+      }),
+      parseReq: ({params, query}) => [params.block_id, query.indices],
+      schema: {
+        query: {indices: Schema.UintArray},
+      },
+    },
   };
 }
 
diff --git a/packages/api/test/unit/beacon/oapiSpec.test.ts b/packages/api/test/unit/beacon/oapiSpec.test.ts
index 15a10bfeb6f7..f7d6cb9a077c 100644
--- a/packages/api/test/unit/beacon/oapiSpec.test.ts
+++ b/packages/api/test/unit/beacon/oapiSpec.test.ts
@@ -130,12 +130,6 @@ const ignoredProperties: Record<string, IgnoredProperty> = {
    */
   getHealth: {request: ["query.syncing_status"]},
 
-  /**
-   * https://github.com/ChainSafe/lodestar/issues/6185
-   *  - must have required property 'query'
-   */
-  getBlobSidecars: {request: ["query"]},
-
   /* 
    https://github.com/ChainSafe/lodestar/issues/4638 
    /query - must have required property 'skip_randao_verification'
diff --git a/packages/api/test/unit/beacon/testData/beacon.ts b/packages/api/test/unit/beacon/testData/beacon.ts
index 7fa8368c590b..6d6bc6576f56 100644
--- a/packages/api/test/unit/beacon/testData/beacon.ts
+++ b/packages/api/test/unit/beacon/testData/beacon.ts
@@ -71,7 +71,7 @@ export const testData: GenericServerTestCases<Api> = {
     res: undefined,
   },
   getBlobSidecars: {
-    args: ["head"],
+    args: ["head", [0]],
     res: {executionOptimistic: true, data: ssz.deneb.BlobSidecars.defaultValue()},
   },
 
diff --git a/packages/api/test/utils/checkAgainstSpec.ts b/packages/api/test/utils/checkAgainstSpec.ts
index ed65279bca22..c887f66e95e6 100644
--- a/packages/api/test/utils/checkAgainstSpec.ts
+++ b/packages/api/test/utils/checkAgainstSpec.ts
@@ -199,12 +199,21 @@ function prettyAjvErrors(errors: ErrorObject[] | null | undefined): string {
   return errors.map((e) => `${e.instancePath ?? "."} - ${e.message}`).join("\n");
 }
 
+type StringifiedProperty = string | StringifiedProperty[];
+
+function stringifyProperty(value: unknown): StringifiedProperty {
+  if (typeof value === "number") {
+    return value.toString(10);
+  } else if (Array.isArray(value)) {
+    return value.map(stringifyProperty);
+  }
+  return String(value);
+}
+
 function stringifyProperties(obj: Record<string, unknown>): Record<string, unknown> {
   for (const key of Object.keys(obj)) {
     const value = obj[key];
-    if (typeof value === "number") {
-      obj[key] = value.toString(10);
-    }
+    obj[key] = stringifyProperty(value);
   }
 
   return obj;
diff --git a/packages/beacon-node/src/api/impl/beacon/blocks/index.ts b/packages/beacon-node/src/api/impl/beacon/blocks/index.ts
index f2e29f00fe57..6fde04bc737c 100644
--- a/packages/beacon-node/src/api/impl/beacon/blocks/index.ts
+++ b/packages/beacon-node/src/api/impl/beacon/blocks/index.ts
@@ -406,7 +406,7 @@ export function getBeaconBlockApi({
       await publishBlock(signedBlockOrContents, opts);
     },
 
-    async getBlobSidecars(blockId) {
+    async getBlobSidecars(blockId, indices) {
       const {block, executionOptimistic} = await resolveBlockId(chain, blockId);
       const blockRoot = config.getForkTypes(block.message.slot).BeaconBlock.hashTreeRoot(block.message);
 
@@ -418,9 +418,10 @@ export function getBeaconBlockApi({
       if (!blobSidecars) {
         throw Error(`blobSidecars not found in db for slot=${block.message.slot} root=${toHexString(blockRoot)}`);
       }
+
       return {
         executionOptimistic,
-        data: blobSidecars,
+        data: indices ? blobSidecars.filter(({index}) => indices.includes(index)) : blobSidecars,
       };
     },
   };