The Bulgarian-Serbian wars are a series of conflicts between the Bulgarian Empire and the medieval Serbian states of Raška, Duklja, and the Kingdom of Serbia between the 9th and 14th centuries in western Serbia, Bosnia, and Kosovo in the western Balkans.Before the 12th century, the Serbian states are dependent upon and strongly influenced by the dominant Balkan powers, the Bulgarian and Byzantine Empires.

The rulers of both these countries seek to control Serb princes to use them as allies in the Byzantine-Bulgarian Wars.

The first war between Bulgarians and Serbs occurs during the reign of Khan Presian between 839 and 842, precipitated by Byzantine diplomacy.

Later, after series of campaigns, the Bulgarian Emperor Simeon I destroys the Serb state in 924.

The Bulgarian Emperor Peter I grants formal independence to Serbia in 931 and appoints his protégé Časlav Klonimirović as its ruler.

They are again subjected by Emperor Samuil in 998.In the 13th century, Stefan Dragutin and his brother Stefan Milutin fight against the Bulgarian governors of Belgrade and Braničevo, Darman and Kudelin and manage to defeat them.

In 1327 the Emperors of Bulgaria and Byzantium sign an anti-Serbian alliance to stop Serbia's growing power but in 1330 Bulgarian Emperor Michael III Shishman is defeated by Stefan Dečanski in the battle of Velbazhd.