A two-dimensional elastic-plastic finite element analysis is performed for plane stress conditions with 4-node isoparametric elements to investigate the closure behavior under various variable-amplitude loading, i.e., single overloading, Hi-Lo block loading, and narrow- and wide-band random loading. The closure behavior under single overloading and Hi-Lo block loading can be well simulated by applying the concept of the most appropriate mesh size that will provide numerical results consistent with experimental data under constant-amplitude loading. It is found that the crack opening load under random loading may be predicted approximately by replacing the complicated random load history with the appropriate equivalent, simplified variable load history.