The present disclosure provides an integrated design building block with turnable modules inside, the building block comprising: a lower housing, an upper housing, and a plurality of turnable modules mechanism, the lower housing and the upper housing being fitted to form a plurality of receiving spaces, the plurality of turnable modules being disposed within the plurality of receiving spaces, respectively, wherein the turnable modules may be partially or completely received in the receiving spaces, the turnable modules each having a turnable module connection portion; the lower housing and the upper housing are fitted to form a body structure of the building block; a plurality of connection portions are provided on surfaces of the body structure; the turnable module connection portions are fitted to the plurality of connection portions on the surfaces of the body structure. The building block provided by the present disclosure has advantages of a simple mechanical structure and a low cost. The present disclosure further provides a building set.