Ivan Antonovich Yefremov was born on April 22, 1908, in Vyritsa, Saint Petersburg, Russian Federation (then Saint Petersburg Governorate, Russian Empire). His father, Antip Haritonovich (then Anton Haritonovich) was a tenant of the Vyritsa sawmill. However, during the Russian Revolution, Yefremov's parents divorced. His mother married a Red Army commander and left the children in Kherson to be cared for by an aunt who soon died of typhus.
Yefremov's abilities to write and study shew up early enough: at the age of four he was able to read and at the age of six he became acquainted with the works of Jules Verne and fell in love with books about explorers, navigators and scientists. During his childhood, Yefremov also "added" a year to his age to start working earlier.