The invention provides a parking device and a speed changer. The parking device comprises a
ratchet wheel, a
ratchet pawl, a
ratchet pawl returning component, a
locking mechanism and a driving mechanism, wherein the ratchet pawl is rotatably connected to a shell of the speed changer and can be switched between an unlocking position and a locking position back and forth, the ratchet wheel is relatively fixedly arranged on an input shaft or an output shaft of the speed changer, the side, facing the ratchet wheel, of one end of the ratchet pawl forms a clamping tooth, the side, facing back to theratchet wheel, of the clamping tooth forms a pressure bearing portion, the
locking mechanism comprises a
cam shaft, a position-limiting plate, a
cam and an
energy storage component, the position-limiting plate is fixed to the
cam shaft, the cam is rotatably arranged on the cam shaft in a sleeving manner, and the
energy storage component is connected between the position-limiting plate and the cam. The parking device is simple and compact in structure, convenient to install and good in overall performance, the parking reliability can be effectively improved, furthermore, the parking device iseasy to fabricate and control and low in production cost, and large-scale promotion and application can be performed.