Yevgeny Dzhugashvili is demanding 11 million rubles ($388,000) in compensation for the comment allegedly made by journalist Nikolay Svanidze on a show aired on Ekho Moskvy radio station May 21, 2010.
Svanidze was reportedly referring to an order signed by Stalin in which he allowed the shooting of children over 12, who were accused of being "enemies of the people".
The journalist has said he was speaking metaphorically.
This is not the first lawsuit filed by Dzhugashvili against Russian media outlets.
In December 2009, he filed a $353,000 suit against the radio station after one of its journalists allegedly said that no "bastard" would dare justify Stalin for sanctioning the killing of children.
Dzhugashvili, however, lost the previous Ekho Moskvy suit and a similar suit against the Novaya Gazeta newspaper.
Published 25 March 2011, 05:30 IST