Leipzig now have 62 points with three games left. Leipzig remain comfortably on course for a return to the Champions League, having already made the quarter-finals this season, with points cushion over closest pursuers Borussia Moenchengladbach and Bayer Leverkusen who played at the weekend.
Spanish midfielder Olmo found the net after nine and 11 minutes while substitute Christopher Nkunku was close to a third in stoppage time when a shot came off the post.
"The most important thing was the three points," Leipzig's Lukas Klostermann told DAZN as his team stretched their unbeaten run to 12 games.
"We could have done better. But the will and attitude worked, so it was deserved in the end."
Hoffenheim went into the game in seventh place and well-placed to still push for a Europa League spot.