A medical device is provided including a base member and a coating layer containing an antithrombogenic material and covering a surface of the base member. The antithrombogenic material contains a copolymer having a repeating unit (A) represented by the following formula (1): wherein R11 is a hydrogen atom or a methyl group, Z is an oxygen atom or —NH—, R12 is a C1-6 alkylene group, R13 and R14 are each independently a C1-4 alkyl group, and R15 is a C1-2 alkylene group, and a repeating unit (B) represented by the following formula (2): wherein R21 is a hydrogen atom or a methyl group, R22 is a C1-6 alkylene group, and R23 is a C1-4 alkyl group. The repeating unit (A) is contained in a proportion of 1 to 7 mol % based on all the structural units of the copolymer.