diff --git a/src/controllers/SettingsController.ts b/src/controllers/SettingsController.ts
index dd02d22..61df94a 100644
--- a/src/controllers/SettingsController.ts
+++ b/src/controllers/SettingsController.ts
@@ -270,6 +270,12 @@ export class SettingsController {
 	 */
 	public static async UploadCustomEmoji(h: RequestHandler) {
 		const shorcut = h.postEmojiShorcut("shorcut");
+
+		// Check if the user has already a shorcut with the same name
+		if(await CustomEmojisHelper.HasUserSimilarShorcut(h.getUserId(), shorcut)) 
+			h.error(401, "A custom emoji with the same shorcut is already defined!")
+		
+
 		const path = await h.savePostImage("image", "custom_emojies", 72, 72);
 
 		// Create the emoji
diff --git a/src/helpers/CustomEmojisHelper.ts b/src/helpers/CustomEmojisHelper.ts
index cb7b3cc..c7d1090 100644
--- a/src/helpers/CustomEmojisHelper.ts
+++ b/src/helpers/CustomEmojisHelper.ts
@@ -29,6 +29,24 @@ export class CustomEmojisHelper {
 		)
 	}
 
+
+	/**
+	 * Check if a given user has already a custom emoji with
+	 * the same shorcut
+	 * 
+	 * @param userID Target user ID
+	 * @param shorcut The name of the shorcut to check
+	 */
+	public static async HasUserSimilarShorcut(userID: number, shorcut: string) : Promise<boolean> {
+		return await DatabaseHelper.Count({
+			table: EMOJIS_TABLE,
+			where: {
+				user_id: userID,
+				shorcut: shorcut
+			}
+		}) > 0;
+	}
+
 	/**
 	 * Get the list of emojies of a given user
 	 *