Although Ti‐V based high‐temperature alloys are used in aerospace engine, rocket engine and hot sections, the structure and mechanical properties of Ti‐V alloys remains controversy. To explore the correlation between structural and mechanical properties, we apply employed the DFT method to study the phases stability, mechanical and thermodynamic properties of Ti‐V solid solution. Two Ti‐V solid solutions: Ti(V)ss solid solution and V(Ti)ss solid solution are discussed. Two Ti‐V solid solutions are thermodynamic stability. In particular, the Ti‐V solid solution prefers to form V(Ti)ss solid solution, in while the V(Ti)ss solid solution remains cubic structure. Furthermore, the Ti(V)ss solid solution is a mechanical instability. However, the V(Ti)ss solid solution is a mechanical stability. Here, the bulk modulus, shear modulus and Young's modulus of V(Ti)ss solid solution are 136.9, 23.5 and 66.7 GPa. In particular, the bulk modulus of V(Ti)ss solid solution is higher than the bulk modulus of the pure Ti. In addition, the V(Ti)ss solid solution shows better ductility compared to the pure Ti and V. Naturally, the stability and mechanical properties of V(Ti) solid solution is related to the Ti‐V metallic bond because of the localized hybridization between the Ti(3d) and V(3d).