Metal-organic frameworks due to their unique properties have many applications. Before using, metal-organic frameworks should be activated and there pores should become empty. ZnO nanoparticles can be prepared by calcination of non-active or activated metal-organic frameworks. In this paper, we wish to have a review on our recent research results in the field of using metal-organic frameworks as new precursors for the preparation of ZnO nanostructures. The results show that non-active metal-organic frameworks are appropriate precursors for the preparation of spherical ZnO nanoparticles but in their active forms, they tend to form agglomerated nanostructures. It can be said that if the number of organic components used in the structure of a metal-organic framework is greater; ZnO nanoparticles with a smaller size will result from it.