| Competition: | Indonesian Super League U-21 |
| Pixels: | 125 |
| Season: | 2009-10 |
| Winners: | Pelita Jaya U-21 |
| League Topscorer: | Aditya Putra Dewa (10 goals) |
| Matches: | 100 |
| Nextseason: | 2009–10 |
The 2008–09 Indonesia Super League U-21 season will be the first edition of Indonesia Super League U-21 (ISL U-21), a companion competition Indonesian super league that are intended for footballers under the age of twenty-one years.
Djarum, an Indonesian tobacco company will continue its participation as the competition's main sponsor.
The competition is divided into three acts consist of two round the group and knockout round. The first round is divided into three groups each containing six clubs, two top teams of each group advanced to the second round. The second half consisted of two groups containing three teams in each group intended, the two best teams from each group advanced to the semifinals. The winner advanced to the final semi-final, while two teams who defeated third-ranked fight. Final winner becomes the champion.
| Grup I | Grup II | Grup III | |
|---|---|---|---|
| Pelita Jaya U-21 | Persib Bandung U-21 | PSM Makassar U-21 | |
| Persita U-21 | Persela U-21 | Persipura U-21 | |
| Persija Jakarta U-21 | Persik Kediri U-21 | Persiba U-21 | |
| Persitara U-21 | Arema FC U-21 | Deltras Sidoarjo U-21 | |
| Sriwijaya FC U-21 | PSIS Semarang U-21 | Persiwa Wamena U-21 | |
| PSMS Medan U-21 | Persijap U-21 | Bontang FC U-21 |
| Rank | Pemain | Klub | Jumlah Gol |
|---|---|---|---|
| 1 | Aditya Putra Dewa | PSM Makassar U-21 | 9 |
| 2 | Rudi Geovani | Persib Bandung U-21 | 7 |
| Rishadi Fauzi | Persita U-21 | 7 | |
| 3 | Yongky Ariwibowo | Persik kediri U-21 | 6 |
| Gherry Setya | Pelita Jaya U-21 | 6 | |
| Riski Novriansyah | Pelita Jaya U-21 | 6 | |
| 4 | Alan Aronggear | Persipura U-21 | 5 |
| Taqwa Ihlas | PSM Makassar U-21 | 5 | |
| Maulana | Persita U-21 | 5 | |
| Aan Andikl Prayitno | Persik Kediri U-21 | 5 |