Due to the electron deficiency caused by the empty p-orbitals of the boron atom and the metallic properties of boron derivatives, organoboron reagents have unique reaction characteristics and important applications in organic chemistry, biomedicine, green chemistry, polymer synthesis and so on. In this section, we will introduce the unique properties of organoboron reagents to solve the difficulties in traditional polymer synthesis: a novel organoboron photocatalyst is constructed to realize the inner-sphere electron transfer mechanism for controlled radical polymerization, the initiation and chain-end reduction of organoboron reagent in controlled radical polymerization are realized by boron radical chemistry, the synthesis of boron-containing polymer is further introduced, and finally the liquid phase synthesis based on organoboron reagent is introduced to achieve the precise polymer synthesis.