To provide an instant film unit using a skirt which is not broken from perforation even when vibration or impact is given without making resistance at the time of breaking the skirt larger.

In this instant film unit, the skirt for capturing excess developing processing solution bonded at the rear end of a photosensitive sheet is stapled on a film pack, and the photosensitive sheet is drawn out by breaking the skirt along the perforation formed on the skirt. A break induction part long lengthwise and nearly parallel with a draw-out direction is formed by the perforation, and its width is ≥1 mm, and its length is ≥1 mm and larger than the width.