Disclosed is a pressure control method capable of performing wound treatment by using a cover unit, a tube member and a pressure control module, the method comprising: (a) the pressure control module forming a pressure having a first pressure value at the wound via the tube member and the cover unit； (b) within a first period of time, increasing the pressure from the first pressure value to a second pressure value； (c) within a second period of time, decreasing the pressure from the second pressure value to a third pressure value； (d) after the pressure has been increased from the third pressure value to a target pressure value, the pressure control module stopping increasing the pressure； (e) sampling a value from the pressure to form a sampled pressure value； and (f) according to the sampled pressure value, determining whether to perform a pressure boost process or perform step (e).
