The present invention is related to a credit card storing metal case, especially a portable device that provides storage of personal belongings, immediate access, convenience and security. The metal case, depending on practical needs, can be carried with personal accessories, like belts and backpacks, to possess great portability; or properly combined with indoor decorations and furniture, like sofas and chair armrests, to achieve a proper storage effect. Especially, the metal storing device is a grooved case with a case insert or a snap-lock mechanism comprising a notched base unit and a cover can provide space for the storage of carried personal belongings such as credit cards and business cards. Thus, the metal case provides great benefits because the user can have easy access to the stored object with great mobility, convenience and security.