The present invention is a system for performing coating and developing treatment for a substrate, which comprises a treatment section having a coating treatment unit for forming a coating film on the substrate, a developing treatment unit for developing the substrate, a thermal treatment unit for performing thermal treatment for the substrate, and a first carrier unit for carrying the substrate into/out of these coating treatment unit, developing treatment unit, and thermal treatment unit. The system of the present invention further comprises an interface section having a second carrier unit for carrying the substrate through a route at least between the treatment section and an exposure processing unit provided outside the system for performing exposure processing for the substrate. The system of the present invention still further comprises a pressure reducing and removing unit for removing impurities adhering to the coating film on the substrate by suction in a chamber before the substrate is subjected to the exposure processing. According to the present invention, before exposure processing, impurities at molecular level such as oxygen, ozone, and organic substances and impurities such as particulates which adhere to the coating film of the substrate can be removed, whereby exposure processing is suitably performed, resulting in a rise in yield.