The utility model provides a sealing structure of a pressure sensor. Housing comprising a sensor, the lower end part of the end button is inserted into the top opening of the shell and is matched withthe shell; a sensitive element is arranged in the shell; an O-shaped sealing ring is arranged between the lower end of the sensitive element and the shell; a circle of step structure is arranged on the inner wall of an opening in the top end of the shell, the lower end of the terminal is located on the step structure, the thickness of the lower end of the terminal is larger than the width of thestep structure, and it is guaranteed that one part of the lower end of the terminal is located above the step structure and the other part is located above the sensitive element and presses the sensitive element. Steps are designed in the shell of the structure. According to the pressure sensor, the O-shaped sealing ring can be compressed in a reasonable range when the shell is subjected to pressure riveting, meanwhile, the sensitive element is prevented from being crushed through shell step limiting, a pressing ring on an original pressure sensor is omitted, the production efficiency of the sensor can be effectively improved, the size of the sensor can be reduced, and the cost of the sensor is reduced.