Betis started strongly with Juanma and Jefferson Montero seeing efforts deflected behind, but it was the visitors who took control as Juanlu opened the scoring with a volley that went through the legs of Betis goalkeeper Casto on 33 minutes.
Levante's fourth successive league win saw them leapfrog Betis in the standings, although the margin of victory should have been greater after Arouna Kone fired straight at Casto when clean through.
The hosts had suffered their first defeat of the season against Getafe on Monday night and they looked keen to put that disappointment behind them as they controlled the early stages.
Juanma was first to threaten but his shot from outside the area was tipped over by Munua before Roque Santa Cruz shot wide.
Levante soon came out of their shell though and the pace of Kone began to stretch the home defence, although their goal came thanks to a couple of errors from the hosts.
First Benat Etxebarria handed the ball to Kone when in comfortable possession and then from Valdo's cross from the left, Juanlu's effort went straight through the goalkeeper.
Kone got in behind the Betis defence minutes later thanks to a great through ball from Jose Barkero but the Ivorian shot wastefully at Casto.
Betis then came close to an equaliser just before the break as Jonathan Pereira's effort was well turned away by Munua and luckily for the goalkeeper went to one of his defenders rather than Santa Cruz.
Betis completely dominated possession in the second period but, like so many others this season, found Levante extremely difficult to break down.
An excellent passing move involving Benat and Salva Sevilla nearly unlocked the door but Juanma miscontrolled when presented with the opportunity of a clear run at goal.
Sergio Ballesteros then produced a brilliant saving challenge on Alex Pozuelo before Nacho's late effort was pushed away by Munua.