In this paper, the piezoresistive effect of the multiwalled carbon nanotube (MWCNT) film is studied. Carbon nanotubes are synthesized by hot filament chemical vapor deposition. The piezoresistive effect in the MWCNT film is studied by a three-point bending test. The gauge factor of the MWCNT film under 500 microstrain is found to be at most 120 at room temperature, exceeding that of polycrystalline silicon (30) at 35℃. The origin of the piezoresistivity in MWCNT film is also discussed.