The invention provides a special vibration testing device for a thermal field emission electron gun, in particular to vibrating a thermal field emission electron gun to be tested and measuring the tiny vibration displacements of different parts of the electron gun relative to excitation positions, and belongs to the field of testing equipment. The device includes a laser vibrometer, an adjustment seat for a vibrometer, a vibration isolation platform, a specimen clamping assembly, a vibrator body, a fixed table, a clamping-loading mechanism, a frame beam, a guide rail bracket, a frame brace, Diagonal support, loading rod, loading platen, loading hanger, guide rail slider module, vacuum chamber cover, terminals, vacuum chamber, observation window, specimen clamping sleeve, vacuum pipe interface. The present invention also provides a special vibration test method for a thermal field emission electron gun based on the above-mentioned device, which extracts vibration information from the test results of the test piece and the test piece holding sleeve through simple data processing, and cooperates with the above-mentioned device to make The test results are closer to the actual working conditions of thermal field emission electron guns.