A connector is configured to be connected to a syringe assembly provided with at least one syringe having an outer cylinder with a protruding tube-shaped port, and a holder which holds the syringe. The connector includes a connector main body mountable on a container containing a medical solution a tube-shaped fitting section protruding from the upper section of the connector main body for receiving the syringe to connect the inside of the syringe and the inside of the container when the syringe port is fitted in the fitting section and fixing means having a lock mechanism that fixes the syringe assembly to the connector main body when the syringe port is fitted in the fitting section, an operating section to release the fixed state provided by the lock mechanism, and a push-out section that pushes out the syringe assembly when the fixing releasing operation is performed.