A calibration apparatus which estimates a calibration parameter of an image acquisition apparatus, comprises a calibration jig which includes at least two planes and in which calibration markers having known three-dimensional positions are arranged in each plane based on a predetermined rule. The calibration apparatus further comprises a calibration marker recognition section configured to measure and number in-image positions of the calibration markers in at least one image obtained by photographing the calibration jig by the image acquisition apparatus, and a parameter estimate section configured to estimate the calibration parameters of the image acquisition apparatus by the use of the three-dimensional position and the in-image position of the calibration markers numbered by the calibration marker recognition section.