The present invention discloses a hydraulic unit of an anti-lock brake system for vehicles having a housing that is easily manufactured, whereby production efficiency is improved, and thus the manufacturing costs of the housing are reduced. The present invention also discloses a method of manufacturing the same. The hydraulic unit comprises a housing having components that control braking oil pressure supplied to wheels of a vehicle, such as a plurality of valves, accumulators, and hydraulic pumps, mounted thereto, flow channels formed in the housing, the flow channels being connected between the components, and a plurality of pipes connected to each other in the housing. The housing is made of an injected resin material having bores and flow channels formed therein. The components are inserted in the bores of the housing. The components are fixedly mounted to the housing by means of fixing members attached to the housing.