A lens apparatus includes: a switch for switching between single and plural modes for using lens apparatus singularly and plurally, respectively; a communication unit to communicate with external device; a unit to set all elements to first state in single mode and set the respective elements to second or third state in plural mode; a control source output unit to output, for each state of the elements, control source information for determining a control command to drive the element; and a unit to determine a command for controlling drive of the elements based on the control source information determined by the control source output portion, wherein in the second state, control commands for corresponding elements are output to other lens apparatuses through the communication unit, and in the third state, the control source output portion outputs control source information different from that in the first and second states.