Cavity revolving plastic injection mould is consisted of top and bottom cavities and core. The feature is that the end of the bottom cavity is installed on the revolving part, ejector rod is under the gate of bottom cavity, on the supporting plate of bottom cavity is the ejector cam insert, of which the bevel is connected with ejector rod .This type of injection mould adopts to cavity rotating without oscillating bar. Injection machine is correspond with the size of product, taking advantage of the equipment. The ejector rob take up the gate of product, then making the product unscrew from the bottom cavity smoothly, ensuring the automatic production. This new kind technique overcome the existing problems, assuring the high efficiency of production.