Cheating on tests is a serious problem in education. The purpose of this study was to test the efficacy of a modified form of the theory of planned behavior (TPB) to predict cheating behavior among a sample of Saudi university students. This study also sought to test the influence of cheating in high school on cheating in college within the framework of the TPB. Analyses were conducted on a sample of 322 undergraduate students using structural equation modeling. The results were consistent with the TPB model's predictions. The TPB model explained a modest variance in cheating in college. When cheating in high school added to the model, the proportion of explained variance increased and cheating in high school was the best predictor of cheating in college. Although not hypothesized by the TPB, subjective norm had a direct effect on attitude.