Along with the Japanese release of the PC version of Gurumin in Japan, Nihon Falcom also released the official soundtrack to the game. Unfortunately, the Gurumin OST was never released outside of Japan.
The Gurumin OST was composed by Hayato Sonoda, Wataru Ishibashi, and Takahide Murayama, with contributions by Icarus Watanabe, Kazuko Ito, Ayako Shibazaki, and Kohei Wada. The soundtrack contains two disks, with the first disk containing 23 tracks, and the second disk containing 19 tracks. While the rear cover art lists disk 2 as only having 18 tracks, it in fact contains a secret 19th track, which is a version of the Tiese Shopping District Theme with vocals. The total runtime of disk 2 is approximately 53 minutes and 49 seconds. The total runtime of disk 2 is approximately 58 minutes and 31 seconds.
Disk 1[]
| Track | Runtime | English Title | Japanese Title |
|---|---|---|---|
| 1 | 2:01 | Guruguru Tonight | ぐるぐるTonight |
| 2 | 1:44 | Phantom Days | オバケな日々 |
| 3 | 1:28 | Who Are You? | あなたはだぁれ？ |
| 4 | 1:58 | My Kind of Phantoms | マイベースなオバケたち |
| 5 | 1:44 | Tiese Shopping District Theme | ティ―ス商店街のテーマ |
| 6 | 2:06 | Banquet Hall | 宴の館 |
| 7 | 1:01 | EURO BEAT POCO | EURO BEAT POCO |
| 8 | 1:23 | T-T-T-Terrible! | たたた大変でしゅ |
| 9 | 0:15 | The Legendary Drill | 伝説のドリル |
| 10 | 2:48 | The Phantom World | オバケワールド |
| 11 | 0:59 | Stage Clear | ステージクリア |
| 12 | 2:00 | Nightmists | 闇の霧 |
| 13 | 1:45 | Something Terrible! | なんだか大変!? |
| 14 | 2:03 | Animal Minimal | Animal Minimal |
| 15 | 3:52 | Plop! Goes the Whirling Wizard | グルグル魔人でポン |
| 16 | 4:11 | Back the Way You Came! | 今来た道を戻れ |
| 17 | 1:59 | Can't Smash My Invincible Armor! | 無敵の鎧は絶対破れマセ～ン！ |
| 18 | 2:44 | The Silence of Negative Ions | マイナスイオンの静寂 |
| 19 | 2:57 | Secret Jungle Survival | 秘密の密林サバイバル |
| 20 | 2:51 | Dance in the Forest | dance in the forest |
| 21 | 3:55 | Rainbow-Colored Phantoms Can't Swim | 虹色オバケは泳げない |
| 22 | 3:42 | Sight of Silence | sight of silence |
| 23 | 4:18 | SAMURAI DRILL! | SAMURAI DRILL！ |
Disk 2[]
| Track | Runtime | English Title | Japanese Title |
|---|---|---|---|
| 1 | 2:36 | JunJun - Jungle Gym | JunJun - Jungle gym |
| 2 | 2:52 | Under the Sky | under the sky |
| 3 | 3:23 | Bomber Girl | bomber girl |
| 4 | 3:17 | Memories | おもひで |
| 5 | 4:18 | The Mysterious Phantom Egg | 不可思議オバケ卵 |
| 6 | 2:24 | Blast of Wind | Blast of Wind |
| 7 | 1:48 | Rocky Nebula | Rocky Nebula |
| 8 | 2:57 | Ode to Revenge | 復讐の賛歌 |
| 9 | 2:52 | The Cursed Fang | 呪われし厄の牙 |
| 10 | 4:41 | Soaring Through the Melancholy Skies | 悲しき蒼穹を翔ける |
| 11 | 2:02 | I Guess I'll Have to! | やるしかないわね！ |
| 12 | 2:30 | The Fight Ends and Night Falls | 戦い終わって日が暮れて |
| 13 | 3:52 | Tomorrow We'll All Be Friends | 明日はきっとみんな友達 |
| 14 | 2:42 | To the Place We Used to Go to | いつもの場所へ |
| 15 | 4:59 | Friends | Friends |
| 16 | 2:25 | TO MAKE THE END OF DIGGING | TO MAKE THE END OF DIGING |
| 17 | 2:03 | Guruguru Tonight (No Vocals) | ぐるぐるTonight -Less Vocal Ver.- |
| 18 | 4:59 | Friends (No Vocals) | Friends -Less Vocal Ver.- |
| 19 | 1:44 | Tiese Shopping District Theme (Vocal) | (Unlisted Secret Track) |