A universal motorcycle storage case mounting assembly that detachably secures to a motorcycle or other vehicle, allowing a user to safely transport personal belongings to a destination. The mounting assembly utilizes two main components—a base frame and a platform, with a storage case being couplable to the platform, forming a transportable storage case. In order to secure to a motorcycle or other vehicle, the mounting assembly utilizes a triple-locking system, including a base latch bracket that attaches to the motorcycle; a receipt on the platform; and a platform latch bracket, the receipt and the platform latch bracket configured to secure the platform to the base frame. As a result of the locking system, the storage case requires force to detach from the motorcycle, thereby preventing inadvertent detachment. Upon arrival at a destination, a rider can detach the transportable storage case, rather than leave belongings on the motorcycle.