Russian general Matvei Platov had eight Cossack regiments and two Don batteries deployed south of the village of Mir, when one brigade of the Polish Fourth Light Cavalry attacked his advance posts, numbering about 100 men. These advance posts had the dual job of both observation and sentry duty, and to entice the enemy to attack; ambushes of a hundred men each were set up farther down the road to Mir, on either side of it. The Polish general Alexander Rosniecki's forces clashed with Russian Alexander Vasilchikov's cavalry, resulting in hand-to-hand combat with fairly even losses. Followed by Uhlans, they swept through the village, attacking Platov's main force. A third Polish brigade attempting to join the fight was encircled and broken by Cossacks, after which the entire Polish force gave ground, driven back with the aid of Russian Hussars. After the arrival of Vasilchikov's AkhtyrkaHussars, Dragoons, and other reinforcements, the battle raged for six hours, shifting to the nearby village of Simiakovo. Platov defeated the enemy there, and moved on to Mir, where he inflicted further losses on the enemy before tactically withdrawing. A complete rout was only averted by Tyszkiewicz's brigade, which covered the Polish retreat.
After retreating from Mir, the castle there was destroyed with gunpowder. The town of Mir and fort ruins were used as a headquarters by Jérôme Bonaparte, on his way to Moscow.