An optical accessory having a high optical performance arranged to change an optical characteristic of a shooting lens and to be attached on the object side of a shooting lens is provided. The optical accessory FE is to be detachably attached to the object side of a master lens M and has at least one lens FE having a negative refractive power. The image-side surface r2 of the lens FE is designed to have an aspherical shape having a negative refractive power that decreases toward its periphery.