Disclosed is a pressure control method capable of performing wound treatment by using a cover unit (12), a tube member (14, 14') and a pressure control module (16), the method comprising: (a) the pressure control module (16) forming a pressure having a first pressure value at the wound (2) via the tube member (14, 14') and the cover unit (12)； (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 (16) 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).
