To provide a gear pump for carrying high viscous liquid, which keeps a bearing in a free state and enhances reliability relative to a leakage of cooling medium and a leakage of molten resins. The gear pump in which a pair of gear rotors 2 are supported on a body 1 of the gear pump through a bearing 6, a cover for preventing the bearing 6 from being slipped out is secured to the body 1, and a temperature adjusting medium passage 20 is formed in the bearing 6, wherein an inlet pipe 28 and an outlet pipe 29 to the temperature adjusting medium passage 20 are connected to the axial outer end of the bearing 6, an intermediate plate 10 is interposed between the axial outer end of the bearing 6 and the cover 11, the intermediate plate 10 being provided with an insert hole 31 for the inlet pipe 28 and the outlet pipe 29, the cover 11 being provided with a guide portion 32 having the inlet pipe 28 and the outlet pipe 29 loosely fitted therein to guide them to outside. Further, at least a part of the inlet pipe 28 and the outlet pipe 29 is formed from a flexible member.