A vertical spring support device for a coupler, comprises a support platform, a bracket, a support rod, a support spring, a wear sleeve and a locknut; the support spring is sheathed on the support rod, and an upper end of the support spring is resisted against a lower surface of the support platform while a lower end of the support spring is resisted against an upper end face of the bracket; an upper end of the support rod is fixedly connected to the lower surface of the support platform, while a bottom end of the support rod passes through the bracket and is then in threaded connection to the locknut via the wear sleeve; the support platform comprises a vertical support platform plate and a horizontal support platform plate, and a lower surface of the horizontal support platform plate is fixedly connected to the upper end of the support rod; and, the vertical support platform plate is vertically fixed on one side of the horizontal support platform plate close to the buffer shell