The invention belongs to the technical field of robot-assisted three-dimensional printing, and discloses an integrated three-dimensional printing system and method for a large-size complex surface conformal antenna. The system involves a sliding guide rail module and a three-dimensional printing module, wherein the sliding guide rail module is used for fixing a to-be-printed working area; and thethree-dimensional printing module is used for realizing printing of a conductive material, and when printing of the to-be-printed area is completed, the three-dimensional printing module moves to thenext to-be-printed area, and completes the printing task until printing of all to-be-printed areas is completed. According to the system and method, a six-degree-of-freedom mechanical arm is adopted,in three-dimensional space, the six-degree-of-freedom mechanical arm can meet the requirements of posture adjustment, and can reach any position in the printing range at any position and posture; a single-degree-of-freedom linear guide rail is adopted, so that the three-dimensional printing working space of the mechanical arm is remarkably expanded; three groups of array nozzles are adopted, different from the single nozzle and single jet hole in traditional curved surface three-dimensional printing, the array nozzle groups greatly improve the printing efficiency, and the array nozzle groups work independently and do not affect each other.