| Sommatiwongse Varodaya | |
| Prince of Nakhon Si Thammarat | |
| House: | Chakri dynasty |
| Father: | Chulalongkorn (Rama V) |
| Mother: | Savang Vadhana |
| Birth Date: | 9 June 1882 |
| Birth Place: | Bangkok, Siam |
| Death Place: | Bangkok, Siam |
Prince Sommatiwongse Varodaya, The Prince of Nakhon Si Thammarat (Thai: สมมุติวงศ์วโรทัย;) was the Prince of Siam (later Thailand). He was a member of the Siamese royal family and a son of King Chulalongkorn Rama V of Siam.
His mother was Queen Savang Vadhana, a daughter of King Mongkut (thus his father's half-sister) and Princess Piyamavadi
Prince Sommatiwongse Varodaya died on 17 June 1899 at the age 17.