The invention discloses a collaborative stressing method for two rows of support cushions of a pier top during cantilever erection of a steel-truss beam, and belongs to the technical field of bridge engineering. The method comprises the steps that in the cantilever erection of the steel-truss beam, a rear row of support cushions are arranged firstly on the pier top of a continuous pier; after several intersegments of cantilever erection, along with the development rule of cantilever erection deformation, a second front row of support cushions are additionally arranged on the pier top of the continuous pier; compaction is not needed firstly during mounting of the front row of support cushions while a gap with the width of 1-2mm is reserved; along with the continuous cantilever erection of the steel-truss beam, the front row of support cushions are gradually compacted, and the borne load gradually becomes heavy; therefore, due to the collaborative stressing of the two rows of support cushions, the loads borne by the two rows of support cushions in the maximum cantilever erection state are equivalent, so that the stress state of a pier top area structure during cantilever erection of the steel-truss beam is improved, and the construction risk is reduced.