To provide a damping device having an inner structure capable of shortening length of the whole damping device, reducing the number of part items to reduce cost, and achieving excellent maintenance performance.

This damping device comprises a bulkhead 13, two cylinder tubes 11a and 11b respectively coupled on both sides of the bulkhead 13, a piston rod 14 penetrating the bulkhead 13 to be slidable along an inner wall of the bulkhead 13, a first piston 14a installed at one end of the piston rod 14, a second piston 17 provided at the other end, a first oil chamber A and a second oil chamber B formed between the bulkhead 13 and the first piston 14a/second piston 17, an oil passage 13b installed inside the bulkhead 13 to communicate the first oil chamber A with the second oil chamber B, and a plurality of damper valves 19a and 19b provided in the oil passage 13b.