This research focuses on the field of intelligent building material spraying, aiming to design an intelligent spraying system based on the S7-1500 controller and ROS laser navigation robot. Through in-depth research on the overall system architecture, implementation of key technologies, algorithm flow, program design, and actual application effects, this paper elaborates on how the system achieves efficient, accurate, and intelligent building material spraying operations. This paper innovatively introduces key common technical elements such as PLC, real-time data perception, cloud storage, intelligent spraying, control of spraying process parameters, ROS, and consistency of the spray coating quality into the building material spraying process, and explores the relevant application technologies in detail. The comparison of actual application data shows that the system has achieved remarkable results in terms of spraying efficiency, quality, and cost control, improving the degree of production automation and reduce labor costs, providing strong support for the intelligent development of the building material spraying industry.