The invention relates to a battery flattening and compacting machine, which comprises a rack, a worktable, positioning devices and a flattening and compacting device; the worktable, the positioning devices and the flattening and compacting device are arranged on the rack; the positioning devices comprise a horizontal positioning device and a vertical positioning device; a guide rail is arranged between the horizontal positioning device and the vertical positioning device; the horizontal positioning device comprises two horizontal positioning parts; the two horizontal positioning parts are respectively and symmetrically arranged at two sides of the guide rail; the worktable is movably arranged on the guide rail; the vertical positioning device is located above the worktable; the flattening and compacting device comprises two flattening and compacting mechanisms; the two flattening and compacting mechanisms are respectively and symmetrically arranged at two sides of the worktable by taking the guide rail as the center, and can move towards the direction of the vertical positioning device. The battery flattening and compacting machine disclosed by the invention has the advantages that a to-be-flattened and compacted battery can be flattened and compacted compactly and flatly, the length of cells of the to-be-flattened and compacted battery and the specific distance of flattening and compacting the cells at the left end and the right end of the to-be-flattened and compacted battery can be accurately controlled, the operation is simple and convenient, and the flattening and compacting quality is high.