Abstract: In this paper the structure and coloration mechanism of spinel cobalt blue pigments are introduced. Recent research progress of synthesis methods and technologies of cobalt blue pigment are summarized，in terms of the preparation methods of nano-materials. These processes include solid phase reaction process，liquid phase reaction process and gas phase process. The solid phase reaction process is commonly used in industry because of its simple technology，but the particle size，color，stability of pigment can not fully meet the market demand. High quality cobalt blue pigments can be prepared by the liquid phase reaction process or gas phase process，but both processes are complex and expensive. The research directions and application prospects of cobalt blue pigments are also presented.