Lewandowski netted for the ninth game running in Europe's elite club competition – becoming the only player to achieve such a streak twice – with a sensational overhead kick in the Olympic Stadium snow.
Bayern, needing only a point to secure first place, was far from comfortable, but Kingsley Coman doubled its lead before half-time to ensure Denys Harmash's belated response counted for little.
Difficult conditions under foot hindered the quality of the contest with one obvious exception. Lewandowski had plenty to do after the ball looped up off Illia Zabarnyi in the area, but his acrobatic finish was emphatic.
That goal was almost cancelled out in farcical fashion, however, as Leon Goretzka prodded towards Manuel Neuer and was grateful to see the post come to his rescue when the goalkeeper failed to make any contact at all with an attempted clearance.
Instead, shortly after Lucas Hernandez survived a tangle with Vitaliy Buyalskiy inside his own area, Thomas Muller dummied Corentin Tolisso's pass and Coman fired in Bayern's second.
Again Dynamo might have responded as Neuer scrambled to save Mykola Shaparenko's deflected effort early in the second half, but the same man could not turn in the rebound.
The home side finally found a way to goal for the first time in this campaign as substitute Harmash nutmegged Neuer, although it lacked the class to then add an equaliser that was perhaps merited, even if Viktor Tsygankov's speculative late strike clipped the post.