The invention relates to a numerical control laser automatic tooth preparation method and equipment thereof. The equipment contains an intraoral spatial digitizer, a dental laser, a numerical control laser tooth preparation control system intraoral working end, an oromaxillo-facial region cone-beam CT machine, a computer, a tooth fixator and a negative pressure aspirator. The computer is respectively connected with the intraoral spatial digitizer, the dental laser, the oromaxillo-facial region cone-beam CT machine and the negative pressure aspirator. The dental laser is connected with the numerical control laser tooth preparation control system intraoral working end which is connected with the tooth fixator. The equipment can replace part of manual operation of a doctor. A traditional mechanical grinding apparatus is replaced with laser. Clinical therapy operative level of grass-roots doctors can be effectively raised within a short period of time, and diagnosis and treatment efficiency and quality can be improved.