Abstract:TA15 alloy samples with different forging passes and deformation temperature were prepared by multidirectional forging process. Using metallographic observation, EBSD, grain size statistics and qusai-static tensile test, the microstructure morphology, grain size, phase content, misorientation angles and mechanical properties during deformation process were analyzed. The experimental results show that a significant equiaxed structure of TA15 alloy is obatained after multidirectional forging at mediun temperature of 700 ℃, and the ratio of high angle boundary increased. Moreover, after 3 pass deformation the average grain size of primary α phase can be refined to 6.0 μm. Besides the deformation microstructure is (α+β) phase, the content of β phase increases compared with initial microstructure. With the increasing of deformation temperature, the grain size increases at 800 ℃ and 900 ℃, but is still smaller than the intial sample. The tensile strength has been improved significantly after multidirectional forging, correspondingly after 3 pass MDF at 700 ℃, the tensile strength of the samples is increased to 1443 MPa and the elongation is 13.6%, which have been slightly lower than the as-received sample. Deformation sample at 900℃,tensile strength is 1178 MPa, the elongation is increased to 15.8%. Finally, comprehensive properties of materials are significantly improved