To provide a simulator program and a recording medium by which the operations of a controller for controlling an engine and a control panel are confirmed without using a real device.

The subject is solved by making a computer including a storage device and an operation processor for checking operation of the controller for controlling the engine and operation panel function as: a controller simulator means 21 for building up the controller; a control panel simulator means 22 for building up the control panel; and an engine simulator means 20 for virtually building up an engine, receiving a request from the controller simulator means 21, and responding to the controller simulator means 21 in accordance with the request.