To propose a crack progress prediction method for accurately predicting progress of cracks generated in a structure, and reducing the processing time.

The method for predicting the progress in the crack C generated in a plate structure M(A) under a predetermined load condition includes a first process of obtaining a stress state under the predetermined load condition, while the crack C is not present in the plate structure M(A); a second process of obtaining stress intensity factors in an opening mode and an in-plane shearing mode at a leading end C1 based on the stress state obtained in the first process, while a virtual crack D for linearly connecting a tail end C0 and the leading end C1 of the crack C is present in the plate structure M(A); and a third process of obtaining the direction for maximizing a circumferential stress at the leading end C1, based on the stress intensity factors obtained in the second process.