For the flue gas desulfurization(FGD) of circulating fluidized bed(CFB), the integrative process of desulfurization and dust extraction has many advantages of simple system, low cost, low maintenance cost, and high desulfurization efficiency ect. By the test analysis of the operation problems of CFB-FGD in the power plant, the causes and corresponding measures are put forward, providing references for design and operation of CFB-FGD system.