The present invention provides a heat-resistant DNA polymerase mutant with high amplification activity. Particularly, the present invention uses protein directed evolution technology to construct a random mutation library for the polymerase active domain of Taq enzyme, and gradually adds screening pressure, so that unsuitable mutations will be eliminated naturally, and mutations with dominant traits will gradually accumulate. Finally, a series of amino acid sites and their mutations that are critical to Taq enzyme amplification and polymerization performance will be selected, and a Taq enzyme mutant with high amplification activity will be obtained.
