The invention discloses a large-mass test part mounting device on a vibration centrifuge. An electric vibration table is arranged on a rotating arm of the vibration centrifuge, and one end of a test part is mounted on the face of the electric vibration table; an auxiliary expansion table is mounted on the rotating arm, one side face of the auxiliary expansion table is close to one side face of the test part, and a gap is reserved between the one side face of the auxiliary expansion table and one side face of the test part; a hydrostatic bearing is mounted on one side face of the auxiliary expansion table, a clamp is mounted on the other opposite side face of the hydrostatic bearing, and one side face of the test part is mounted on the clamp; the manner of combining the hydrostatic bearing and the auxiliary expansion table is adopted to bear gravity or centrifugal force borne by the test part, and the test part cannot be completely mounted on the face of the electric vibration table. The clamp, the hydrostatic bearing and the auxiliary expansion table are mounted on the rotary arm, the load capacity of the test part is obviously improved, and the effective quality of the test part and the whole test capacity of the vibration centrifuge can be obviously improved.