To provide a lens device enabling an operator to suitably instruct the moving direction of automatic focusing(AF) and capable of suitably detecting the operator's instruction by setting up an AF stand-by state for waiting for the operator to instruct the AF moving direction by operating a focus operation member when the start of the AF mode is instructed in an AF mode enabling the operator to instruct the AF moving direction.

When the start of the AF mode is instructed by an AF mode start switch S1, a CPU 100 switches a clutch FCL to the manual side and waits for the operator to instruct the AF moving direction by operating a focus ring FR. When the AF moving direction is instructed, the CPU 100 switches the clutch FCL to the power side, drives a focus driving motor FM, moves a focus lens F to the instructed AF moving direction, starts AF processing on the basis of a focus evaluation value obtained from a gate circuit 124, and at the time of detecting a focusing position, sets up the lens F on the focusing position.