An all-polarization-maintaining erbium-doped mode-locked fiber laser based on carbon nanotube was designed and built. The output power was 2.141 mW, the repetition rate was 61.6924 MHz, the spectral center wavelength was at 1563.94 nm, and the full width at half maximum was 7.031 nm. The environmental stability of the laser in vibration is studied. The femtosecond fiber laser was placed on a shaking table to perform the identification-grade sinusoidal vibration test with accelerations up to 12g and the identification-grade random vibration test with root mean square acceleration of 12.81grms in the X, Y, and Z directions, respectively. After each test, the mode-locked threshold power, output power, signal-to-noise ratio of the mode-locked signal, repetition rate, center wavelength, and spectral width were measured. It was found in the experiment that the laser after vibration can still be stable in the mode-locked state, and the optical performance was not changed. This study provides an important reference for future spaceborne mode-locked fiber laser sources.