Among the double perovskite oxides, Sr2CrReO6 has been attractive a lot of attention due its half-metallic ferrimagnetic nature and the highest magnetic transition temperature of 635 K. Here, we systematically investigated the influence of uniaxial strain along [100]-direction on the electronic and magnetic properties of double perovskite oxide Sr2CrReO6 using first-principle calculations. Our results show that a critical tensile strain of +2% leads the system to the ferromagnetic metallic state from half-metallic ferrimagnetic with a spin-polarization of 64%. Because, tensile strain decreases the anti-ferromagnetic coupling between Cr and Re ions, which results in ferromagnetic ordering. The admixture of Cr/Re dx2−y2, dxz, and dyz orbitals are mainly responsible for metallicity. Along with this, the total magnetic moment gets enhanced and almost close to an integral value of 5 μB for higher tensile strains. On the other hand, compressive strains exhibit no substantial impact on the physical properties of Sr2CrReO6. Moreover, it is also found that spin-polarization optimized with a further increase of tensile strains. Close to half-metallic ferromagnetic state due to tensile strain, this material shows a wide range of scientific and technological applications in spintronics.