The Battle of Chernavchitsy was fought on 20 June 1655 when a Polish-Lithuanian army defeated a fourth Swedish army sent to relieve the besieged fortress of Berestye (Brest, Belarus).
On 18 June, the Poles destroyed three Swedish relief armies at the Battles of Brest, Ozyaty, and Žabinka. Two days later, a fourth Swedish relief army under General Gustaf Evertsson Horn marched on Berestye from the north. The Polish armies besieging Berestye once again lifted their siege in order to intercept the Swedes. In the ensuing battle, the Polish cavalry drove off the Swedish reiters but suffered heavy casualties at the hands of their pikemen. Ultimately, Poland's numerical superiority carried the day, and Horn's army was annihilated. Despite an impressive run of victories around Brest, the Poles would shift their strategy towards securing their borderland with Minsk's recapture before refocusing on capturing Brest and driving north into Lithuania.