Mazepin covered 4474 km in 34 hours 41 minutes and 32 seconds.
The second was Armen Puzyan from the Nakusi Racing team (35:21.06), the third was Mazepin's teammate Sergey Karyakin (35:32.57).
The Silk Way Rally Marathon runs from 6 to 16 July with a start in Astrakhan and a finish in Moscow.
Earlier it was reported that the crew of the KAMAZ-master team led by Dmitry Sotnikov won the eighth stage of the Silk Way rally-raid in the trucks standings.