diff --git a/prisma/dbml/schema.dbml b/prisma/dbml/schema.dbml
index d546b66..2567404 100644
--- a/prisma/dbml/schema.dbml
+++ b/prisma/dbml/schema.dbml
@@ -369,6 +369,7 @@ Table user_logs {
 Table collections {
   id String [pk]
   name String [not null]
+  slug String [not null]
   medias medias [not null]
   owner users [not null]
   ownerId String [not null]
@@ -379,6 +380,10 @@ Table collections {
   deletedAt DateTime
   createdAt DateTime [default: `now()`, not null]
   updatedAt DateTime [default: `now()`, not null]
+
+  indexes {
+    (slug, ownerId) [unique]
+  }
 }
 
 Table watch_histories {
diff --git a/src/modules/collection/controllers/addItemToCollection.controller.ts b/src/modules/collection/controllers/addItemToCollection.controller.ts
index 5024e0e..00a5885 100644
--- a/src/modules/collection/controllers/addItemToCollection.controller.ts
+++ b/src/modules/collection/controllers/addItemToCollection.controller.ts
@@ -1,10 +1,23 @@
 import { Context, Static } from "elysia";
 import { returnWriteResponse } from "../../../helpers/callback/httpResponse";
 import { addItemToCollectionSchema } from "../schemas/addItemToCollection.schema";
+import { addItemToCollectionService } from "../services/addItemToCollection.service";
+import { mainErrorHandler } from "../../../helpers/error/handler";
 
 export const addItemToCollectionController = async (ctx: {
   set: Context["set"];
   headers: Static<typeof addItemToCollectionSchema.headers>;
+  params: Static<typeof addItemToCollectionSchema.params>;
+  body: Static<typeof addItemToCollectionSchema.body>;
 }) => {
-  return returnWriteResponse(ctx.set, 200, "Item added to collection successfully" + ctx.headers.cookie);
+  try {
+    const savedItem = await addItemToCollectionService({
+      cookie: ctx.headers.cookie,
+      collectionName: ctx.params.name,
+      mediaId: ctx.body.itemId,
+    });
+    return returnWriteResponse(ctx.set, 200, "Item added to collection successfully", savedItem);
+  } catch (error) {
+    return mainErrorHandler(ctx.set, error);
+  }
 };
diff --git a/src/modules/collection/repositories/UpsertUserCollection.repository.ts b/src/modules/collection/repositories/UpsertUserCollection.repository.ts
new file mode 100644
index 0000000..5c8157b
--- /dev/null
+++ b/src/modules/collection/repositories/UpsertUserCollection.repository.ts
@@ -0,0 +1,43 @@
+import slugify from "slugify";
+import { AppError } from "../../../helpers/error/instances/app";
+import { prisma } from "../../../utils/databases/prisma/connection";
+import { generateUUIDv7 } from "../../../helpers/databases/uuidv7";
+
+export interface UpsertUserCollectionRepositoryPayload {
+  userId: string;
+  collectionName: string;
+  mediaConnectId: string;
+}
+
+export const upsertUserCollectionRepository = async (payload: UpsertUserCollectionRepositoryPayload) => {
+  try {
+    return await prisma.collection.upsert({
+      where: {
+        slug_ownerId: {
+          slug: slugify(payload.collectionName, { lower: true }),
+          ownerId: payload.userId,
+        },
+      },
+      update: {
+        medias: {
+          connect: {
+            id: payload.mediaConnectId,
+          },
+        },
+      },
+      create: {
+        id: generateUUIDv7(),
+        name: payload.collectionName,
+        slug: slugify(payload.collectionName, { lower: true }),
+        ownerId: payload.userId,
+        medias: {
+          connect: {
+            id: payload.mediaConnectId,
+          },
+        },
+      },
+    });
+  } catch (error) {
+    throw new AppError(500, "Failed to upsert user collection");
+  }
+};
diff --git a/src/modules/collection/services/addItemToCollection.service.ts b/src/modules/collection/services/addItemToCollection.service.ts
new file mode 100644
index 0000000..dff1e06
--- /dev/null
+++ b/src/modules/collection/services/addItemToCollection.service.ts
@@ -0,0 +1,15 @@
+import { parse } from "cookie";
+import { jwtDecode } from "../../../helpers/http/jwt/decode";
+import { tokenValidationService } from "../../auth/services/http/tokenValidation.service";
+import slugify from "slugify";
+
+export type AddItemToCollectionPayload = {
+  cookie: string;
+  collectionName: string;
+  mediaId: string;
+};
+
+export const addItemToCollectionService = async (payload: AddItemToCollectionPayload) => {
+  const { auth_token } = parse(payload.cookie);
+  return (await tokenValidationService(auth_token as string)).user.id;
+};