In the high-end equipment manufacturing fields of aerospace, shipping, wind power, etc., there exist several technical challenges, such as the large machining stroke, high reachability, high rigidity, high precision and economic effectiveness, which bring performance balancing problems for machining systems of CNC machine tools or industrial robots. Mobile robot manufacturing system becomes an effective solution to large structural parts manufacturing, but how to ensure the machining quality and make the machining intelligent remain a challenge. Therefore, an unmanned intelligent machining technology framework for mobile robots is proposed in consideration of the machining performance constraints and the motion characteristics. Correspondingly, an integrated autonomous intelligent machining tasks are constructed, including autonomous positioning, high stiffness positioning, in-situ measurement, autonomous planning, intelligent machining, and quality inspection. Aiming at the curved surface machining inside large cylinders, an autonomous intelligent mobile robot machining system is developed under the proposed framework and task. The experiment results show that the mobile robot machining system can realize high quality machining intelligently.