By different heat treatment technologies and microstructural analysis methods, microstructure characteristics of equiaxed structure, duplex structure and lamellar structure for TC4 titanium alloy was observed in this study. Meanwhile, the influence of different microstructure on tensile property and fatigue property was studied. The results show that: equiaxed structure with the finest α grain and high dislocation density exhibits the highest strength;Duplex structure, with bigger α phase and lower dislocation density than that of equiaxed structure, presents excellent process plasticity; Lamellar structure, with coarse original β grain, presents the lowest plasticity. While, the lamellar structure presents the best fatigue property. When crack size is lower than 250?m, the crack growth rates of three microstructures are obviously different. The lamellar structure exhibits the lowest crack growth rate, and it is the highest for equiaxed structure. When crack size is higher than 250?m, there is no obvious different. Because of good comprehensive mechanical properties, duplex structure will be used in fastener manufacturing.