:In view of the problem of shrinkage，inclusion and segregation in the as cast high entropy alloy，the CoCrFeNiTi x (x = 0 to 1. 2) alloys were synthesized by mechanical alloying (MA) and spark plasma sintering (SPS)，and the effects of Ti on the microstructure and mechanical properties of alloys were investigated systematically. Phase structure and microstructure of CoCrFeNiTi x alloys were investigated by using Metallurgical Microscope，X-ray Diffraction and Scanning Electron Microscope. Simultaneously，the hardness and compressive strength of the alloys were also tested. The results show that，there was major FCC phase in the alloys synthesized by SPS. Meanwhile，there exist a small amount of Laves，σ，and Ｒ phase. Further，the grain size of the alloy becomes smaller with the increase of Ti content. The hardness and compressive strength of the CoCrFeNiTi x highentropy alloys show the trend of increasing first and then decreasing with the increase of Ti content. When x reaches1，the CoCrFeNiTi alloy possesses a higher hardness level of 670 Hv. Meanwhile，when x reaches 0. 6，compressive strength of the CoCrFeNiTi 0. 6 alloy has the maximum value of 600 MPa.