The precision of crack-propagation prediction is improved by taking into consideration a variation in the error due to inspectors and inspection methods. There is provided a crack-propagation prediction method including a correlation-information preparing step of measuring the length of a crack initiated in a test object by a plurality of inspectors and/or a plurality of inspection methods and obtaining correlation information between data acquired through the measurement and the condition of an actual crack; a crack-length estimating step of estimating the actual length of the crack initiated in an inspection target on the basis of the crack length measured by an inspector during inspection of the inspection target and the correlation information; and a crack-propagation-curve estimating step of estimating a crack-propagation curve of the inspection target originating from the crack length estimated in the crack-length estimating step.