The invention provides a wheelset gauge transformation device. The device comprises a plurality of sleepers which are alternately arranged along the first direction, a first guardrail set which is arranged on the sleepers along the first direction, a second guardrail set which is arranged on the sleepers along the first direction, a first unlocking rail which is arranged on the sleepers along thefirst direction, is positioned between the first guardrail set and the second guardrail set and is arranged close to the first guardrail set, a first wear-reduction mechanism which is arranged on oneside of a first gauge-changeable wheel which is arranged on the first side of the first unlocking rail toward a vehicle body, is arranged in a manner of rotating relative to the first unlocking rail and can be used for unlocking the first gauge-changeable wheel through the first wear-reduction mechanism, wherein the first guardrail set and the second guardrail set are arranged oppositely. By adopting the device, the effect of effectively protecting the first unlocking rail can be achieved, and the service life and reliability of the wheelset gauge transformation device can be respectively prolonged and improved.