A lens apparatus comprising a drive controller, said lens apparatus including a first lens unit which is movable in an optical axis direction for changing magnification and a second lens unit positioned on an image plane side with respect to the first lens unit and which is movable in said optical axis direction with the change in magnification so as to prevent an image plane variation caused by the movement of the first lens unit, the drive controller comprising: a driving unit of the second lens unit for moving the second lens unit; a control unit arranged to control said driving unit of the second lens unit so as to prevent an image plane variation caused by the movement of the first lens unit; a memory arranged to store tracking data consisting of a plurality of tracking curves, each tracking curve serving as position data of the second lens unit relative to the first lens unit, for correcting an image plane variation caused by a movement of the first lens unit; and a detecting unit arranged to detect a movement speed of the first lens unit, wherein the control unit is arranged to control the driving unit of the second lens unit so as to drive the second lens unit with a micro-amplitude to search for a position nearer to an in-focus state according to an evaluation value indicating a contrast state of a captured image, in the case that the movement speed of the first lens unit is equal to or lower than a predetermined speed, and wherein the control unit is arranged to control the driving unit of the second lens unit by using the tracking curves, such that the position of the second lens unit is controlled to track a particular tracking curve and the evaluation value indicating a contrast state of a captured image is checked at predetermined intervals such that if the difference between a previous evaluation value and a present evaluation value exceeds a predetermined threshold, the tracking curve used is changed to a different tracking curve for which the evaluation value is higher, in the case that the movement speed of the first lens unit is higher than the predetermined speed. a driving unit of the second lens unit for moving the second lens unit; a control unit arranged to control said driving unit of the second lens unit so as to prevent an image plane variation caused by the movement of the first lens unit; a memory arranged to store tracking data consisting of a plurality of tracking curves, each tracking curve serving as position data of the second lens unit relative to the first lens unit, for correcting an image plane variation caused by a movement of the first lens unit; and a detecting unit arranged to detect a movement speed of the first lens unit, wherein the control unit is arranged to control the driving unit of the second lens unit so as to drive the second lens unit with a micro-amplitude to search for a position nearer to an in-focus state according to an evaluation value indicating a contrast state of a captured image, in the case that the movement speed of the first lens unit is equal to or lower than a predetermined speed, and wherein the control unit is arranged to control the driving unit of the second lens unit by using the tracking curves, such that the position of the second lens unit is controlled to track a particular tracking curve and the evaluation value indicating a contrast state of a captured image is checked at predetermined intervals such that if the difference between a previous evaluation value and a present evaluation value exceeds a predetermined threshold, the tracking curve used is changed to a different tracking curve for which the evaluation value is higher, in the case that the movement speed of the first lens unit is higher than the predetermined speed.