The pressure reducing valve can reduce the inlet pressure to a certain required outlet pressure through adjustment, so that the outlet pressure can be automatically kept stable. Applicable to: pressure reducing valve for pipeline pressure reducing devices such as oxygen, nitrogen, air, argon, steam, etc. The nominal diameter is DN15~DN100, and the nominal pressure is 2.5MPa and 4.0MPa. After adjustment, the outlet pressure can be adjusted to 0.2~2.5MPa.