The invention provides a shock absorber and a car. The shock absorber comprises a hub fixedly arranged on a crankshaft in a sleeving mode, and a primary shock absorption structure and a secondary shock absorption structure are sequentially arranged on the hub from inside to outside. The primary shock absorption structure comprises a rubber ring arranged on the hub in a sleeving mode and a first inertia ring arranged on the rubber ring in a sleeving mode. The secondary shock absorption structure comprises a clutch assembly arranged on the first inertia ring in a sleeving mode and a second inertia ring arranged on the clutch assembly in a sleeving mode. An elastic component is arranged between the clutch assembly and the first inertia ring. The shock absorber and the car can reduce torsional vibration of a crankshaft system of an engine with high power and large torque.