To provide a plastic container, the inside of which is divided into a plurality of compartments via a weakened seal and separate contents are sealed in the compartments, and which enables the confirmation of the presence or absence of unsealing/opening between the compartments via the weakened seal.

The inside of the bag-shape plastic container is divided into a plurality of the compartments with the weakened seal, and marks are put on the inner and outer surfaces of the upper compartment divided into the plurality of comportment with the weakened seal, respectively, so that marks form respective different patterns before and after the communication via the unsealed weakened seal. When the contents sealed separately in the compartments sandwiching the weakened seal are mixed together by unsealing the seal, the unsealing of the seal and mixture of the contents are displayed on the container.