A control device for an automatic transmission is provided, which includes a friction engagement element, and a processor configured to execute gear change control logic configured to control a gear change operation by supplying and discharging hydraulic fluid for forming a gear stage to/from the friction engagement element, and lubricant supply control logic configured to control to switching operation of a supply amount of lubricant to the friction engagement element according to an operating state of a vehicle. The processor controls the gear change operation and the switching operation to not overlap with one another.