The adaptive optical system of a TW chirped pulse amplification laser based on Ti:Sapphire was optimized considering the wavefront distortion due to the focusing system itself. A much smaller focal spot was obtained experimentally, and the energy concentration was improved. The size of the focal spot decreased from 2.3 times the diffraction limit to 1.17 times, and more than 50% of the energy was concentrated in the Airy disk. After optimizing the adaptive optical system, we generated hot electrons using a 4 TW laser system under a relativistic power intensity condition. The proposed laser is expected to offer a better experimental condition for laser-matter interaction.