One of the important aims in the synthesis of zeolite imidazolate framework-8 is to prepare crystals with predictable structures and valuable properties. It is observed that the properties of ZIF-8 have been directly or indirectly determined by various synthetic factors. Among many synthetic factors, solvents and synthesis methods are unavoidable parameters that control the overall structure of ZIF-8. This article presents a deep understanding of how solvents play their role in the crystallization and structure and therefore the properties of ZIF-8 by considering the polarity, viscosity, interfacial tension and molecular structure and comparing the behaviour of each solvent in every synthesis method. Also, to clearly realize their effect on the formation and final properties of ZIF-8, the crystallization process and mass transfer are discussed.