The invention relates the technical field of lead-acid battery detection, and discloses a strength detection device for a lead-acid battery. The strength detection device comprises a bottom plate, wherein an accommodating table is fixedly arranged in the center of the top of the bottom plate; fixed seats are movably arranged on two sides of the bottom plate; insertion boxes are inserted into the tops of the two fixed seats; two sides of the inner cavities of the two insertion boxes are fixedly connected through lower support plates and upper support plates from bottom to top in sequence; motor bases are fixedly arranged in the centers of the tops of the lower support plates; driving motors are fixedly arranged on the tops of the motor bases; output shafts of the driving motors are fixedly connected with lead screws which are rotationally connected with the centers of the bottoms of the upper support plates; the surfaces of the lead screws are in threaded connection with lead screw sleeves. In the strength detection device for the lead-acid battery, the driving motors, the lead screws, the lead screw sleeves, carrying shafts and pressing blocks are provided, so that workers can get an accurate strength value of the lead-acid battery conveniently, and the high quality of the lead-acid battery is ensured.