Controller used for a boom device, the boom device including - a base, - a boom supported by the base and capable of being raised and lowered between a lowered position and a raised position, - a winch having a wire wound around a wire drum and wound around a distal end of the boom, - a load hook provided at a tip of the wire, - a first drive source configured to raise and lower the boom, - a second drive source configured to drive the winch and to unwind the wire from the wire drum or wind the wire around the wire drum, - an engaging member provided on the base and to which the load hook suspended from the distal end of the boom at the raised position is engaged in a detachable manner, - a derrick angle sensor configured to detect a derrick angle (θ)of the boom, and - a length sensor configured to detect an unwinding length of the wire from the distal end of the boom, the controller comprising: - a memory configured to store specified values corresponding to a length of the boom and a position of the engaging member with respect to a derrick fulcrum of the boom, wherein the controller is configured to: calculate a displacement distance from the distal end of the boom to the engaging member based on the derrick angle (θ) of the boom detected by the derrick angle sensor and based on the specified values read out from the memory; and - execute an automatic boom drive process of driving the winch while raising or lowering the boom between the lowered position and the raising position in a state where the load hook is engaged with the engaging member such that the displacement distance is a distance corresponding to the length detected by the length sensor. - a base, - a boom supported by the base and capable of being raised and lowered between a lowered position and a raised position, - a winch having a wire wound around a wire drum and wound around a distal end of the boom, - a load hook provided at a tip of the wire, - a first drive source configured to raise and lower the boom, - a second drive source configured to drive the winch and to unwind the wire from the wire drum or wind the wire around the wire drum, - an engaging member provided on the base and to which the load hook suspended from the distal end of the boom at the raised position is engaged in a detachable manner, - a derrick angle sensor configured to detect a derrick angle (θ)of the boom, and - a length sensor configured to detect an unwinding length of the wire from the distal end of the boom, the controller comprising: - a memory configured to store specified values corresponding to a length of the boom and a position of the engaging member with respect to a derrick fulcrum of the boom, - a memory configured to store specified values corresponding to a length of the boom and a position of the engaging member with respect to a derrick fulcrum of the boom, wherein the controller is configured to: calculate a displacement distance from the distal end of the boom to the engaging member based on the derrick angle (θ) of the boom detected by the derrick angle sensor and based on the specified values read out from the memory; and calculate a displacement distance from the distal end of the boom to the engaging member based on the derrick angle (θ) of the boom detected by the derrick angle sensor and based on the specified values read out from the memory; and - execute an automatic boom drive process of driving the winch while raising or lowering the boom between the lowered position and the raising position in a state where the load hook is engaged with the engaging member such that the displacement distance is a distance corresponding to the length detected by the length sensor.