An ant colony algorithm based cooperative optimization for machining scheme selection and operation sequencing of engine cylinder is proposed. Considering that features have alternative machining schemes, one machining scheme is chosen randomly for every feature in total iterations, and an operatingconstraint matrix is created automatically based on featureconstraint matrix and operation priority. Aiming at minimizing the transforming times of manufacturing resources that contain setups, tools and machine tools, a son optimal solution is found by the ant colony algorithm in the son iteration. In addition, a global optimal process line is ensured to be gotten through the usage of elitist preserving strategy in the total iteration. Finally, an engine cylinder case is illustrated to prove the validity of the proposed method.