The Brave Blossoms scored just the once before half time but added three more tries after the break.
Ayumu Goromaru’s penalty opened the scoring and although it was Japan who were dominating territory, Russia hit back with a try from Vladimir Ostroushko. Ramil Gayshin added the extra two and Kingsley Jones’ side led 7-3.
A break from Goromaru in the 15th minute was finished off by Hendrik Tui and the conversion made it 10-7.
A brace of penalties from Gayshin saw Russia regain the lead before Goromaru’s penalty made it 13-13 at the break.
That was as good as it got for Russia though as they failed to score any second half points.
Michael Broadhurst, who impressed against Wales last summer, crossed two minutes after the break with Goromaru converting and kicking a penalty.
Male Sa’u and Toshiaki Hirose then rounded off the scoring in what was ultimately a comfortable win.
