In this study, a general procedure of fatigue life prediction was developed for structural integrity assessment. Based on fatigue crack growth equations in terms of effective stress intensity range and cyclic J-integral range, fatigue lives under variable loadings were predicted for the random load histories used in the SAE Fatigue Cumulative Damage Test Program. Life prediction was also performed for the case when fundamental data of fatigue crack growth was not available at hand, by estimating fatigue crack growth characteristics. The predicted lives based on the procedure proposed in this study were found to be in good agreement with the experimental results.