Abstract: The RV tank storage rack is adapted to attach onto a rear bumper of an RV, and support a portable sewage tank there from. The RV tank storage rack includes a folding ramp, a tank platform, and a back support frame. The tank platform is positioned between the folding ramp and the back support frame. The tank platform is adapted to receive a portable sewage tank. A mounting member extends from underneath the tank platform. The mounting member is adapted to secure the RV tank storage rack onto a rear bumper of an RV. The folding ramp is hingedly connected with the tank platform, and rotates downwardly in order to adaptively enable the portable sewage tank to be rolled onto or off of the tank platform.