In an apparatus installed on a boat for identifying and controlling operation of an outboard motor selected by an operator and clamped to the boat from among outboard motors in different models prepared to be selectable by the operator, including a model having an analog device that produces analog signal and a model having a digital device that converts the analog signal produced by the analog device into a digital signal, it is discriminated whether the inputted signal is the analog signal inputted through the analog signal input/output or the digital signal inputted through the digital signal input/output, and the model of the selected outboard motor is identified based on the discriminated signal, thereby enabling to surely identify the model and control its operation.