Ivan Martynovich Zarutsky (Заруцкий, Иван Мартынович in Russian) (died 1614) was a Cossack leader in Russia in the early 17th century.
Zarutsky played an important role in creating the military for False Dmitri II and took part in all of his battles, for which he would be given the title of a "boyar".
After the death of the impostor, Zarutsky married Dmitri's widow Marina Mniszech and set the goal to install her son Ivan on the Russian throne.
In January 1611, Zarutsky joined the First People's Volunteer Army, which had been fighting with the Polish invaders in Moscow under the command of Prokopy Lyapunov.
In 1612, abandoning the siege of Moscow, Zarutsky and his cossacks, fled to Kolomna with Marina Mniszech and her son Ivan.