The invention relates to an earth pressure test apparatus under multi-culvert conditions, and an application method thereof. The test apparatus comprises a test case and a lifting device, wherein the bottom portion of the test case is provided with a first unit board and a second unit board, the lifting device comprises a lifting power device, a top pipe landing slab, a top pipe and top pipe moving supports, the top pipe landing slab is lifted up and down through the lifting power device, the top pipe can slide in a sliding groove of the top pipe landing slab, and connection devices are arranged between the adjacent push-pull top pipe moving supports. The method comprises steps that the position of the top pipe is adjusted, the position of the adjacent top pipe moving supports is adjusted, the top pipe is lifted to fix the first unit board, and the first unit board is lifted down gradually to simulate actual work conditions. The method and the device are advantaged in that during culvert earth arch effect tests at different positions, time saving and labor saving are realized, economic property is realized, and the precise result is acquired.