The present invention discloses a quasi-differential capacitive MEMS pressure sensor and manufacturing methods thereof. The quasi-differential capacitive MEMS pressure sensor includes a first lower electrode, a second lower electrode, a first upper electrode supported above the first lower electrode, and a second upper electrode supported above the second lower electrode, wherein the first upper electrode is a pressure-sensitive film, and a cavity between the first upper electrode and the first lower electrode is a closed cavity, so that the first upper electrode and the first lower electrode constitute an air pressure-sensitive type capacitor; and the second upper electrode and the second lower electrode constitute a reference capacitor whose capacitance does not vary with external air pressure. The pressure sensor provided by the present invention can at least partially filter out a common-mode interference signal in an output signal of the air pressure-sensitive type capacitor by use of the reference capacitor, thereby improving the stability and resolution of the output signal of the air pressure-sensitive type capacitor.