We report full potential treatment of electronic, mechanical and magnetic properties of Co2VSi0.5Al0.5 using the linearized augmented plane-waves method (LAPW) provided by Blaha within density functional theory (DFT) using generalized gradient approximation (GGA) for exchange correlation potentials in the parametrization of Perdew. The objective is to seek for stable half-metallic ferromagnets materials with Curie temperatures higher than room temperature. The series of Co2VSi0.5Al0.5 is found to exhibit half-metallic ferromagnetism with high magnetic moment and the localized moment in this magnetic compound resides at the Co atom. It has been observed that our compound have high Curie temperatures with high spin polarizations