To date, hundreds of porous organic frameworks (POFs) have been successfully designed and synthesized. With regard to POFs, the first important problem is the constructing strategies of POFs. In this chapter, we introduce some principles for the synthesis of POF materials. Based on the type of POFs (crystalline or amorphous), the discussion of POFs is classified into two parts. For the synthesis of POF materials, two most vital factors should be followed. One is the monomers that are the fundamental constructing units for the synthesis of POFs, and the other is the polymerization reactions. The structure and property of POFs are determined by the utilization of monomers and polymerization reactions. In other words, the synergistic effect of two factors could influence the chemical and physical characteristics of the resulting samples.