The present invention discloses a multi-pole circuit breaker with auxiliary supports, which comprises a base, a plurality of single-pole circuit breaking units, an operating mechanism and a rotation axis assembly, wherein the rotation axis assembly consists of a plurality of supporting assemblies and a plurality of support shaft parts in series; each of the support shaft parts is provided with a movable contact bridge; each of the supporting assembly consists of a rotation axis, an auxiliary support, an auxiliary support bearing and at least one supporting rod; the rotation axis maintains synchronous revolution with the support shaft parts; the outside of the bearing is tightly assembled with a bearing hole of the auxiliary support, while the inside is tightly assembled with the rotation axis; the supporting rod is tightly assembled with a supporting rod installing hole on the auxiliary support; the operating mechanism is fixedly connected with the supporting rod; and the supporting rod is fixedly installed on a housing of the single-pole circuit breaking unit and provides stable supporting force for the rotation axis through the auxiliary supports. The multi-pole circuit breaker has balanced contact pressure at each contact point, flexible operation, fast breaking, good breaking synchronism of contacts at all poles and long service life.