| Lassi Forss | |
| Birth Date: | 15 January 2002 |
| Birth Place: | Lahti, Finland |
| Position: | Right-back |
| Currentclub: | JIPPO |
| Youthclubs1: | Kuusysi[1] |
| Years1: | 2018 |
| Clubs1: | Kuusysi |
| Caps1: | 3 |
| Goals1: | 0 |
| Years2: | 2019–2021 |
| Clubs2: | Reipas Lahti |
| Caps2: | 21 |
| Goals2: | 1 |
| Years3: | 2019–2021 |
| Clubs3: | Lahti |
| Caps3: | 17 |
| Goals3: | 0 |
| Years4: | 2020 |
| Clubs4: | → MyPa (loan) |
| Caps4: | 8 |
| Goals4: | 0 |
| Years5: | 2022–2023 |
| Clubs5: | Reipas Lahti |
| Caps5: | 44 |
| Goals5: | 3 |
| Years6: | 2024– |
| Clubs6: | JIPPO |
| Caps6: | 4 |
| Goals6: | 0 |
| Nationalteam1: | Finland U19[2] |
| Club-Update: | 29 April 2024 |
Lassi Forss (born 15 January 2002) is a Finnish professional footballer who plays as a right-back for JIPPO in Ykkösliiga.