A camera accessory can be detachably engaged with a camera body that includes a camera body mount, and is equipped with an accessory mount assuming a bayonet structure with a first tab, a second tab and a third tab set over intervals in a circumferential direction running along a circumference of a circle and projecting from the circumference along a radial direction. The accessory mount can be inserted through the camera body mount without any of the first through third tabs being hindered by any of three camera body-side tabs at the camera body mount, as long as the accessory mount is inserted into the camera body mount at a correct interlock phase. The accessory mount includes a restricting member disposed near the third tab.