The invention provides a special trolley suitable for a diversion tunnel large-diameter pressure pipeline, and belongs to the technical field of transportation equipment. The trolley is used for solving the problems of difficult transportation and installation of large-diameter pressure pipelines in a tunnel. The trolley comprises a traveling system, a main beam, a support system, a hydraulic system, and an electrical control system, the traveling system comprises a traveling wheel set, a hydraulic motor and a support platform, the left side of the support platform is provided with a counterweight system, the support system comprises a support frame, a support frame traveling mechanism, horizontal support arms and longitudinal support arm, the main beam is fixedly provided with a support frame travelling hydraulic cylinder, the telescopic end of the support frame travelling hydraulic cylinder is fixedly connected with the support frame travelling mechanism, the horizontal support armsare symmetrically distributed on the left and right sides of the support frame, and the longitudinal support arm is vertically arranged above the support arms. The trolley can realize transportation,adjustment, and installation in place of a pressure steel pipe in the tunnel, is suitable for the loading requirements of pipelines of different sizes, is strong in adjustability, and greatly improvesthe construction efficiency and quality.