Inexpensive two-port solenoid valves that can be connected with five-port solenoid transfer valves are provided. Two valve discs 25A and 25B constituting a two-port valve are inserted into a five-port valve body 15 having a supply channel 21 opened at the center of a valve hole 20; output channels 22A and 22B are opened on the respective sides of the supply channel; and ejection channels 23A and 23B are opened on the respective sides of the output channels. A pilot valve section 12 is used to drive the valve discs. The valve discs 25A and 25B use the fluid pressure in the supply channel 21 as returning force for the valve bodies, and each has seal members 28A and 28B for continuously sealing the portion between the output channels 22A and 22B and the ejection channels 23A and 23B, respectively, regardless of the operating positions of the valve discs; and each also has seal members 29A and 29B for opening and closing the portion between the supply channel 21 and the output channels 22A and 22B, respectively.