The lens drive adapter is detachably attachable to a lens barrel on which an operation member and a lens electric contact portion are provided. The adapter includes a drive unit including a drive member configured to transmit a driving force to the operation member, an adapter electric contact portion configured to contact the lens electric contact portion to be electrically connected therewith, and two adapter coupling portions configured to couple with the lens barrel at its two circumferential locations to fix the adapter to the lens barrel. The adapter electric contact portion is provided, in a first direction corresponding to an optical axis direction of the lens barrel, at a position different from that of the drive member and between the two adapter coupling portions.