There is a rubber sealing ring between the pot cover and the pot, which will not leak. There is an exhaust hole in the middle of the pot cover, which is blocked by a pressure limiting valve similar to a weight. When the pressure cooker is heated (there is water and food in the cooker), when the gas pressure in the cooker rises to a certain degree, the gas will jack up the pressure limiting valve, and the steam can be discharged out of the cooker through the exhaust hole, which will not cause explosion due to excessive pressure in the cooker.