A method for quick forming of a metal sheet. In an embodiment, the method includes the following steps: placing a metal sheet blank to be formed on a forming mold; introducing high-pressure gases with equal pressures simultaneously into upper and lower enclosed cavities respectively formed by the metal sheet blank and the sealing mold, and the metal sheet blank and the forming mold; heating the metal sheet blank to a preset forming temperature condition; quickly releasing the high-pressure gas from the cavity formed by the metal sheet blank and the forming mold, such that the metal sheet blank bulges; and discharging the gas from the cavity formed by the metal sheet blank and the sealing mold, and opening the mold to obtain a formed metal sheet part.