Latos (2-2) allowed only two hits over six innings, fanning 11 batters while issuing a pair of walks in a dominating performance.
The Reds right-hander tossed 68 of his 107 pitches for strikes in racking up his third start without a loss.
J.J. Hoover, Aroldis Chapman and Alfredo Simon wrapped up the game without allowing a hit for the Reds, who won the rubber match of their three-game series at PNC Park.
Drew Stubbs went 3-for-4 with a two-run homer and Todd Frazier also went deep in Cincinnati's win.
Pirates starter Charlie Morton (1-3) yielded five runs (four earned) on seven hits in a six-inning effort.