To provide an integrated type diaphragm device for a camera that suitably obtains a small aperture stop just by devising configuration of a plurality of aperture blades.

A diaphragm driving ring 4 is rotatably attached to a bottom plate 1. An aperture blade 6 is arranged closer to the bottom plate 1 side than an aperture blade 5, and the aperture blades 5 and 6 are paired. Six pairs of aperture blades 5 and 6 are rotatably attached to the bottom plate 1, and their edge sides are set to, what is called, the integrated type and are assembled each other. The aperture blade 5 has ordinary thickness and includes a coupling pin 5b. The aperture blade 6 is thinner than the aperture blade 5, and includes a cam groove 6b. The coupling pin 5b of the aperture blade 5 is inserted to both of the cam groove 6b of the aperture blade 6 and a cam groove 4a of the diaphragm driving ring 4. By such constitution, a large diaphragm aperture is formed by six aperture blades 5, and a small diaphragm aperture is formed by six aperture blades 6.