A portable fuel tank that is configured to be operably secured to an apparatus having a combustible engine so as to provide fuel for the operation thereof. The portable fuel tank includes a body having walls, top and a bottom integrally formed to create an interior volume for receiving and storing fuel. The body has a one-way valve secured to the top thereof. A fuel cap is hermetically sealed to the body and includes a fuel pickup line operably coupled thereto. The fuel transfer line is fluidly coupled to the machine having the combustible engine and includes a one-way valve and a quick connect assembly. Locking tabs are provided to secure a first portable tank to a second portable tank. A mateable fastener is formed in the body of the tank and is configured to be releasably secured to a mateable fastener on the machine.