To provide a simulation device responding to a call of a peripheral device using an IO register and improving the speed of the simulation, a simulation method, and a program.

A CPU simulation unit 20 executes a simulation by simulating a CPU. A peripheral device simulation unit 50 includes one or more components (a timer simulation section 51 and the like) that execute a simulation by simulating a peripheral device to be activated by an access to the IO register. A detection unit 60 is configured to detect the access to the IO register corresponding to the peripheral device when executing the simulation. A connection management unit 70 sets a component to be activated when executing the simulation according to the detection result of the detection unit 60.