A contact module for a circuit breaker is disclosed, comprising: a base, a cover, an operation mechanism, at least three kinds of asymmetrical single-pole switches and a release mechanism. The cover is mounted on the base to form a space, where the mechanisms and the switches are disposed. The operation mechanism is connected to one switch; the release mechanism to the at least three switches. Each switch comprises a strong side and a weak side. For each switch, there is a thick contact housing on the strong side connected to a thick shaft, and a thin one on the weak side connected to a thin shaft. A rotor component has a single contact spring mounted on the weak side. Rotation shafts are connected by a linkage shaft to connect the single-pole switches; a strong side of one switch is connected to a weak side of another switch.