There is disclosed an information processing apparatus which easily acquires calibration information required to transform the measured value of a position and orientation sensor into the position and orientation of an image sensing device on a world coordinate system, without using any special calibration tool. When a position and orientation of the image sensing device by attaching a receiver of a position and orientation sensor which comprises a transmitter and a receiver, approximate calibration information required for a coordinate transformation that transforms the position and orientation of the receiver into those of the image sensing device will be calculated by the following steps. Adjusting the position and orientation of the image sensing device so as to the transmitter of the sensor to be sensed at or near the center of a sensed image, obtaining a measured value of the sensor and calculating the approximate coordinate value based on the measured value storing unit