The Bulgarian–Serbian wars were a series of conflicts between the Bulgarian Empire and medieval Serbian states between the 9th and 14th centuries in the central Balkans.
Before the 12th century, the Serbian states were dependent upon and strongly influenced by the dominant Balkan powers, the Bulgarian and Byzantine Empires. The rulers of both those countries sought to control Serb princes to use them as allies in the Byzantine-Bulgarian Wars. The first war between Bulgarians and Serbs occurred during the reign of Presian between 839 and 842, precipitated by Byzantine diplomacy. Later after series of campaigns the Bulgarian Emperor Simeon I conquered and destroyed the Serb state in 924. The Bulgarian Emperor Peter I granted formal independence to Serbia in 931 and appointed his protégé Časlav Klonimirović as its ruler. The most powerful Serbian state of the time, that of Duklja, was again subjugated by Emperor Samuil in 998.