Based on femtosecond laser inscription technology,a novel method for femtosecond laser micromachining system is proposed to fabricate a microfiber Fabry-Perot (F-P) cavity on the fiber end surface.This technique can solve the parallelism problem of the traditional fiber F-P sensors inscribed by femtosecond laser.The F-P interferometric sensor made by the proposed technique shows over 20 dB fringe visibility.This technique is parameter-controllable and easy to implement.It is a promising candidate of strain measurement in the case of extreme temperature circumstances.