First-principles calculations on mechanical behavior of V-Ta( Ta=0 to~20 wt. %) alloys are performed. Calculated Young's modulus,shear modulus,Cauchy pressure and bulk modulus/shear modulus indicate that as content of Ta is around 10 wt. %,V-Ta alloy shows good mechanical properties with large strength and good ductility. To examine calculation predictions,binary V-Ta alloys including V-10 wt. % Ta,V-15 wt. % Ta,V-20 wt. % Ta were processed and tested at room temperature. Computational results agree with experiment well. It indicates that the approach is a promising way for alloy design.