The present invention provides a filling nozzle obtained by using a resin selected from a cycloolefin polymer and a cycloolefin copolymer, or a filling nozzle including a tubular passage for supplying a pharmaceutical solution, and a filling port disposed at a lower end of the tubular passage, in which the tubular passage and the filling port have a circular peripheral cross-section, and an inner diameter of the passage of the filling port is larger than an inner diameter of the tubular passage disposed on an upstream side.