Gain-guided index-antiguided (GG IAG) fiber has a negative index step from cladding to core, and the gain effect plays a crucial role in guiding mode. It has attractive performance on large mode area of the high-power single-mode fiber lasers. The research progress at home and abroad of GG IAG fiber laser is summarized. At first, the theoretical details of GG IAG fiber laser including bending, mode coupling, gain saturation and thermal characteristics are summarized. Then the experiments of Nd-doped, Yb-doped fiber lasers are presented. At last, the advantages and problems of the GG IAG fiber laser in high power fiber lasers are discussed.