To provide a ceiling installed vehicle air conditioning unit capable of improving air conditioning capability with a simplified construction.

A ceiling installed vehicle air conditioning unit 1 contains an evaporator 15 and a fan 16 and mounts a unit body 3 having an air suction inlet 19 and a blowoff outlet 21 on a ceiling of a vehicle. The evaporator 15 includes many refrigerant tubes P1 to P8 inserted into the laminated fins 23 and these refrigerant tubes are connected with each other to form a refrigerant passage 27. In the refrigerant passage 27 a part extending from the refrigerant inlet to the refrigerant outlet is assumed one refrigerant passage, and the refrigerant tube is branched by a branch tube in the course thereof into a plurality of refrigerant passages to flow a refrigerant.