diff --git a/src/infra/repository/nita.js b/src/infra/repository/nita.js
index 07799ba..d9e099d 100644
--- a/src/infra/repository/nita.js
+++ b/src/infra/repository/nita.js
@@ -2,14 +2,6 @@
 import 'dotenv/config';
 import postgres from 'postgres';
 
-/**
- * @typedef {import('../../types').Nita} InsertNitaParameters
- */
-
-/**
- * @typedef {import('../../types').Nita} UpdateNitaParameters
- */
-
 /**
  * @returns {import('../../types').NitaRepository}
  */
@@ -24,9 +16,6 @@ export const postgresNitaRepository = () => {
   const sql = postgres(config);
 
   return {
-    /**
-     * @param {InsertNitaParameters} params
-     */
     async insertNita(params) {
       const { trackCode, discordUserId, milliseconds, lastMilliseconds } = params;
       const results = await sql`
@@ -34,9 +23,6 @@ export const postgresNitaRepository = () => {
       `;
       return results;
     },
-    /**
-     * @param {UpdateNitaParameters} params
-     */
     async updateNita(params) {
       const { trackCode, discordUserId, milliseconds, lastMilliseconds } = params;
       const results = await sql`
@@ -44,21 +30,18 @@ export const postgresNitaRepository = () => {
       `;
       return results;
     },
-    /**
-     * @param {string} discordUserId
-     * @param {string} trackCode
-     */
     async deleteNita(discordUserId, trackCode) {
       const results = await sql`
         DELETE FROM nita WHERE discord_user_id = ${discordUserId} AND track_code = ${trackCode}
       `;
       return results;
     },
-    /**
-     * @param {string} discordUserId
-     * @param {string} trackCode
-     * @returns {Promise<import('../../types').Nita | null>}
-     */
+    async deleteAllNita(discordUserId) {
+      const results = await sql`
+        DELETE FROM nita WHERE discord_user_id = ${discordUserId}
+      `;
+      return results;
+    },
     async selectNitaByUserAndTrack(discordUserId, trackCode) {
       const results = await sql`
         SELECT milliseconds, last_milliseconds FROM nita WHERE discord_user_id = ${discordUserId} AND track_code = ${trackCode}
@@ -73,10 +56,6 @@ export const postgresNitaRepository = () => {
         lastMilliseconds: results[0].last_milliseconds,
       };
     },
-    /**
-     * @param {string} discordUserId
-     * @returns {Promise<import('../../types').Nita[]>}
-     */
     async selectNitaByUser(discordUserId) {
       const results = await sql`
         SELECT track_code, milliseconds, last_milliseconds FROM nita WHERE discord_user_id = ${discordUserId}
diff --git a/src/slash-command/delete.js b/src/slash-command/delete.js
new file mode 100644
index 0000000..291e662
--- /dev/null
+++ b/src/slash-command/delete.js
@@ -0,0 +1,42 @@
+// @ts-check
+import { SlashCommandBuilder } from 'discord.js';
+import { searchTrack } from '../const/track.js';
+
+/** @type { import('../types').SlashCommand } */
+export default {
+  data: new SlashCommandBuilder()
+    .setName('delete')
+    .setDescription('自分の記録を削除します。コース名に`all`を入力することですべての記録を削除できます。')
+    .addStringOption(option => option.setName('track').setDescription('コース名').setRequired(true)),
+  execute: async (interaction, nitaRepository) => {
+    const trackQuery = interaction.options.getString('track');
+
+    if (!trackQuery) {
+      throw new Error('コース名を指定してください');
+    }
+
+    const discordUserId = interaction.member?.user?.id || interaction.user?.id;
+    if (!discordUserId) {
+      throw new Error('ユーザーIDが取得できませんでした');
+    }
+
+    if (trackQuery === 'all') {
+      await nitaRepository.deleteAllNita(discordUserId);
+      await interaction.reply({
+        content: '全てのタイムを削除しました。',
+      });
+      return;
+    }
+
+    const track = searchTrack(trackQuery);
+    if (!track) {
+      throw new Error(`コースが見つかりませんでした。\n入力されたコース名:  ${trackQuery}`);
+    }
+
+    await nitaRepository.deleteNita(discordUserId, track.code);
+    await interaction.reply({
+      content: `${track.trackName}のタイムを削除しました。`,
+    });
+    return;
+  },
+};
diff --git a/src/types.d.ts b/src/types.d.ts
index 84dbcca..2b7a8b5 100644
--- a/src/types.d.ts
+++ b/src/types.d.ts
@@ -17,6 +17,7 @@ export type NitaRepository = {
   insertNita: (params: InsertNitaParameters) => Promise<any>;
   updateNita: (params: UpdateNitaParameters) => Promise<any>;
   deleteNita: (discordUserId: string, trackCode: string) => Promise<any>;
+  deleteAllNita: (discordUserId: string) => Promise<any>;
   selectNitaByUserAndTrack: (
     discordUserId: string,
     trackCode: string