Titanium alloys exhibit great potential for applications in various engineering fields due to their excellent comprehensive properties, whereas the lower elastic modulus significantly limits their usage in structural parts that require for high strength and high rigidity of materials. In order to develop high elastic modulus titanium alloy with good comprehensive mechanical properties, Ti-6Al-4Mo-xMn (x=0, 1, 2, 3, 4 wt.%) alloys were prepared by a cold crucible suspension melting method. The effect of Mn content on the microstructure and mechanical properties of the alloy was systematically investigated. The results demonstrated that the prepared Ti-6Al-4Mo-xMn alloys were composed of α and β phases without Ti-Mn phase impurity. With the increase of Mn content, the α→β phase transition temperature decreased, resulting in an increase in volume fraction of β phase. Moreover, the microstructure of the alloys gradually became finer and evolved toward Widmannstatten microstructure. The hardness of the alloy increasesd from 30 HRC to 46 HRC; and the tensile strength increased from 838 MPa to 1266 MPa, which is because solution strengthening and microstructure refinement caused by Mn atoms. With the increase of Mn content, the elastic modulus of the alloy increased first and then decreased. When the Mn content is 1%, the elastic modulus of the alloy exhibited a highest, value of 136 GPa, and the tensile strength was 916 MPa, which are 24.0% and 3% higher than those of Ti-6Al-4V alloy, respectively.