Abstract: A vacuum pumping apparatus includes a pump housing 1 and a motor housing 8. The housings 1 and 8 are fastened together so as to be a sealed structure by O-rings 51-58 interposed therebetween. A shaft 17 of a driving device 70 and a driving shaft 15 carrying a rotor 2a are detachably connected via a coupling 91. During operation of the apparatus, a rotor chamber 41 in the pump housing 1 and a motor chamber 43 in the motor housing 8 are equalized in pressure, which requires no mechanical seal therebetween. The coupling 91 facilitates easy removal or detachment of a motor part B from a pump part A, which results in convenient maintenance of the pump part A.