Atom transfer radical polymerization (ATRP), as a new type of controllable/living polymerization reaction, has been applied in many fields widely, such as the structure design of the polymer,the surface modification of inorganic materials, protein detection, biopolymer separation, antibacterial and antifouling, etc. Three major factors are involved in the reaction process:monomer, initiator system (initiator, catalyst, complexant), and reaction medium, the core element of which is the choice of ATRP initiator. The microstructure and performance of the initiator are the key factors for the ATRP reaction. In this paper, we firstly introduce the types and properties of the micromolecule initiator and the reaction mechanism of the ATRP briefly. Then,we emphatically summarize the latest advances about the preparation methods of the ATRP macromolecular initiator in recent years, such as functional group reaction, coupling reaction and free radical polymerization. Moreover, we also review the latest application of the macromolecular initiator through ATRP reaction in the structure design of the polymer, the surface modification of inorganic materials and biological materials. Finally, an outlook for the prospective development of the ATRP initiator system is given.

Contents
1 Introduction
2 Small molecular initiator
3 Preparation of the macromolecular initiator
3.1 Functional group reaction method
3.2 Coupling reaction method
3.3 Free radical polymerization method
4 Application
4.1 Structure design of the polymer
4.2 Surface modification of inorganic materials
4.3 Surface modification of biomolecular
5 Conclusion