Equipped with a tilt mirror and micro-mirror replacing the moving mirror, a novel Fourier transform spectrometer is proposed based on programmable Micro-Electro-Mechanical Systems(MEMS) micro-mirror. Firstly, the working principle and the tolerance of the tilting mirror is analyzed systematically and validated experimentally. Theory results show that the limited tilt angle is 0.52° and the spectrum resolution is 8 nm in the near infrared region; while the limited tilt angle is 0.183°, the spectrum resolution is 3 nm in the visible region. Experimental measurement shows that the spectra can be reconstructed accurately in the tolerance of the tilting mirror with central wavelength 488 nm laser soure and polychromatic light soure, while distorted badly out of the tolerance range.