| Tvrtko II | |
|---|---|
 Coin of Tvrtko II | |
| King of Bosnia | |
| First reign | 1404–1409 |
| Predecessor | Ostoja |
| Successor | Ostoja |
| Second reign | 1420–1443 |
| Coronation | August 1421 |
| Predecessor | Stephen Ostojić |
| Successor | Thomas |
| Died | November 1443 |
| Spouse | Dorothy Garai |
| House | Kotromanić |
| Father | Tvrtko I of Bosnia |
| Mother | possibly Dorothea of Bulgaria |
| Religion | Roman Catholicism |
Stephen Tvrtko II (Serbo-Croatian: Stjepan/Stefan Tvrtko, Стјепан/Стефан Твртко; died in November 1443), also known as Tvrtko Tvrtković (Твртко Твртковић), was a member of the House of Kotromanić who reigned as King of Bosnia from 1404 to 1409 and again from 1420 to his death.
Tvrtko II was the son of King Tvrtko I. His reigns took place during a very turbulent part of Bosnian history. He was first installed as a puppet king by the kingdom's leading noblemen, Hrvoje Vukčić Hrvatinić and Sandalj Hranić Kosača, to replace his increasingly dependent uncle Ostoja. Five years later, he lost the support of the nobility and thus the crown as well. He was hardly politically active during the second reign of Ostoja, but managed to depose and succeed Ostoja's son Stephen. Tvrtko's second reign was marked by repeated Turkish raids, which forced him to accept the Ottoman suzerainty, and the struggle for power with Radivoj, another son of Ostoja. Tvrtko was married twice, but died childless. He was succeeded by his chosen heir, Radivoj's brother Thomas.