The invention discloses a bracket used for an overlong water pier pre-stress cover beam construction support system. The bracket used for the overlong water pier pre-stress cover beam construction support system comprises two steel inclined struts arranged between two adjacent water piers in reverse V shape and four steel pipe uprights arranged at four sides of each water pier; a pin hinge and a support thereof are connected with the bottom end of each strut rod, and the pin hinge support at the bottom end of each steel strut is connected with a bearing platform of the corresponding water pier through a pre-embedded steel plate II; horizontal support cover plates with the same height are arranged at the top ends of the strut rods of the steel inclined struts and the top ends of the steel pipe uprights, and a longitudinal support beam is fixed on each two longitudinally opposite horizontal support cover plates; all the steel pipe uprights and steel inclined struts are connected through horizontal connecting components. The bracket used for the overlong water pier pre-stress cover beam construction support system is strong in bearing ability, high in stability and capable of being used for the overlong water pier cover beam construction support system with more than 40 meters in length, more than 8 meters in mounting height and more than 18 meters in clear distance between pier bodies.