Storage container opening/closing device and storage container opening/closing method

A storage container opening/closing device configured to open and close a storage container comprising a storage portion configured to house a frame member to which a pellicle film is attached, and a cover configured to cover the storage portion, the storage container opening/closing device comprising:

• a storage container support unit configured to support the storage container;
• and
• an opening/closing unit configured to open and close the storage container by moving the cover, wherein
• the opening/closing unit comprises:
• a retainer configured to retain the cover;
• a first movement unit configured to move the cover retained by the retainer in a direction away from and toward the storage portion;
• and
• a second movement unit configured to tilt the cover retained by the retainer with respect to the storage portion.