A wet processing system detects a globule of a process solution in a drippy or dripping state from the tip of any one of process solution pouring nozzles being moved to a pouring position for pouring the process solution onto a substrate by obtaining image data on the process solution pouring nozzle, and takes proper measures to prevent the process solution from dripping. A wet processing system 1 pours a process solution, such as a resist solution, through one of process solution pouring nozzles 10 onto a surface of a substrate, such as a wafer W, held substantially horizontally by a substrate holding device 41 surrounded by a cup 5 to process the surface by a wet process. A nozzle carrying mechanism 10a carries the process solution pouring nozzles 10 between a home position on a nozzle bath 14 and a pouring position above the substrate held by the substrate holding device 41. An optical image of the tips of the process solution pouring nozzles 10 is obtained by an image pickup means, such as a camera 17. Predetermined measures are taken according to the level of a drippy or dripping state of a globule of the process solution.