To prevent a ring member attached to a cap for verifying whether or not the cap is opened from being severed accidentally from the cap of a bottle-shaped container having virgin seal on mounting the cap for the first time onto the container after the container is filled with contents.

A part for screwing the cap 2 down onto a mouth part 4b of the container main body 4 is formed as a screw ring 3 separately from the container main body 4 and made available for mounting by movement in the axial direction onto the container main body 4. Consequently, a marking ring 5 attached to the cap 2 is not affected by any external force on mounting as the mounting is made onto the container main body 4 after the screw ring 3 is screwed down into the cap 2. Therefore, the cap 2 can be fitted onto the container main body 4 without breakage of the marking ring 5.