The invention relates to a two-time demoulding method of a part. The two-time demoulding method needs using a demoulding mold. The two-time demoulding method comprises the following steps that A, pneumatic demoulding is conducted, specifically, a driving mechanism is started, the driving mechanism drives a movable mold to be separated from a fixed mold, a first valve is opened, ventilating is conducted on a communicating pipe, and gas generates push force on the part, so that a gap is formed between the part and the fixed mold; B, pre-separating is conducted, specifically, a control mechanismis started, the control mechanism controls the opening degree of the first valve, and the air inlet amount of a through hole is controlled, so that pressure in the through hole is controlled; and C, pushing for demoulding is conducted, specifically, a jacking rod is pushed to jack the part to be thoroughly separated from the fixed mold. Compared with the prior art, according to the scheme, througharrangement of the through hole, the control mechanism, the jacking rod and the like, the bending problem of the part is prevented, and the demoulding efficiency is further improved.