The invention discloses a roller carrier with pipe fitting welding, pre-cleaning and drying treatment functions. The roller carrier comprises a roller carrier base. Roller carrier bodies are mounted at the two ends of the roller carrier base. A high-pressure water spray mechanism and a rotary brushing mechanism are arranged at the position, between the roller carrier bodies, of the roller carrier base. A cleaning spray head is mounted at the upper end of the high-pressure water spray mechanism. A rotary mechanism is mounted in the rotary brushing mechanism. The output end of the rotary mechanism is coaxially connected with an elastic press rod. The elastic press rod is vertically guided out of the upper end of the rotary brushing mechanism. A brush head is mounted at the top end of the elastic press rod. A dryer shroud is fixedly mounted on the outer side of each roller carrier body. A drying mechanism is mounted on the inner side plate face of the top end of each dryer shroud. In this manner, the roller carrier can be used as a supporting tool during pipe fitting welding and can provide the pipe fitting pre-cleaning and drying service, pipe fittings are subjected to surface cleaning treatment before welding, and welding quality is improved.