Abstract: To promote the mechanical properties of TC19 titanium alloy for rotor of aero-engine, the microstructure and mechanical properties of the alloy are investigated. The metallographic microscope (OM) and transmission electron microscope (TEM) are used to analyze the microstructure and element contents of TC19 alloy bar, and the tensile and creep properties TC19 alloy bar solution treated at different temperatures are tested. The results show that when the solution temperature increases from 900 to 928 ℃, the volume fraction of primary α phase of the TC19 alloy decreases from 25% to 5%, and that its tensile properties at room temperature and at 425 ℃, and its creep property at 455 ℃ decrease slightly. The contribution of grain boundary strengthening is minor, and the solid solution strengthening is dominant. The incoherent interface between α_p phase and β phase, the small width and a great number of interfaces of lamellar secondary α phase in β transformation microstructure, and the high content of alloying elements in β phase contribute to the better mechanical properties of TC19 alloy with 25% content of primary α phase.