With the outbreak of the Russo-Swedish War in 1788, Bibikov volunteered to enter the corps of Lieutenant-General Ivan Michelson, who had served with Bibikov's father and now took the younger Bibikov under his patronage. In the Swedish campaign, Bibikov participated in the reconnaissance of the Swedish outpost at Gokforsky around the village of Kiro, near Wilmanstrand. In a subsequent engagement at the village Bibikov and two grenadiers captured a Swedish cannon. In preliminary operations around Porrassalmi on 1 June 1789, he was wounded in the left leg by a bullet, and in the Battle of Porrassalmi Bibikov commanded a company and was again wounded. For bravery in action he was awarded the Order of St. George Fourth Class on 9 June 1789. He was again in action on 9 July 1789, clashing with Swedish forces as they passed through Kyumen towards Memele, and again at Memele on 29 July. Bibikov then joined the Russian galley fleet, under Vice-Admiral Karl Heinrich von Nassau-Siegen, and distinguished himself at the Battle of Rochensalm in August 1789, and at the disembarkation at the mouth of Kymi on 21 August, where he commanded a battalion of the Preobrazhensky Regiment. For these latter actions he was on 30 August 1789 awarded the ceremonial Golden Sword "For Bravery".