To provide a film unit with a waterproof lens which makes it hard to cause a hand shake in photography and improves the holding certainty of a grip part.

The shape of the grip part 17 of a waterproof case 1 is made large, through holes 3a and 3b are formed in a case body 2a and a lid 2b constituting the waterproof case 1 outside the watertight structure of the waterproof case 1 and inside the external shape of the grip part 17 and aligned successively when the lid 2b is fixed to the case 2a so that a portable strap is inserted to the hole. No projection is formed outside the external shape of the grip part 17 to improve the holding certainty when the grip part 17 is gripped for photography.