Hollow fiber membrane module

A hollow fiber membrane module includes one pressure vessel, and at least one hollow fiber membrane element loaded in the pressure vessel. Each of the element includes a plurality of hollow fiber membranes each having openings at both ends, a bypass tube, and a supply port and a discharge port provided on one end side in a longitudinal direction. The supply port is in communication with inflow-side openings of hollow fiber membranes. The bypass tube is provided in the longitudinal direction of the element, has an inflow port at an end portion on a side of outflow-side openings of the hollow fiber membranes, and has an outflow port at an end portion on a side of the inflow-side openings of the hollow fiber membranes. The outflow-side openings of hollow fiber membranes are in communication with the inflow port, and the outflow port is in communication with the discharge port.