To provide a diaphragm control device of a camera and the camera which can stabilize quality of an image acquired by photographing.

A diaphragm control device of a camera comprises: a rotary weight 551 which is pivotally supported coaxially with an encoder gear 523 and which can rotate relatively with the encoder gear 523; a rotary weight rubber 552 which can rotate integrally with the rotary weight 551; and a rotary weight spring 553 for energizing the rotary weight 551 and the rotary weight rubber 552 against the encoder gear 523 in the diaphragm direction. If vibration is generated at a diaphragm control lever 501 when the diaphragm control lever 501 returns and stops at the position before starting photographing, the rotary weight 551 and the rotary weight rubber 552 rotate in a direction opposite to a rotation direction of the encoder gear 523 by moment of inertia of themselves, to alleviate the vibration of the diaphragm control lever 501.