Personality is a determining factor in moral judgment, emotions, and behaviors. Regardless of what construct of personality affects what ethical variables, an important question is what similarities and differences are among these relationships across cultures. The current study investigates the relationships between moral foundations, work ethics, normal personality factors, dark personality traits, social cynicism, and anomie in an Iranian and a Canadian sample. Although the personality variables’ correlations with moral foundations were different in the two contexts, in both contexts personality was a better predictor than moral foundations in predicting work ethics. Findings in the Iranian sample showed that work ethics was negatively correlated with anomie and Machiavellianism, and positively correlated with Honesty-Humility. In the Canadian sample, work ethics was negatively correlated with psychopathy, and positively correlated with Honesty-Humility, Extroversion, and Conscientiousness. Controlling for job experience did not make any difference in these relationships. Findings of this study support the conclusion that work ethics is a culture dependent construct. In collectivistic cultures such as Iran, ethical decision making and behaviors are mainly influenced by personality factors related to reciprocal altruism and collectivistic values like fairness in interactions with others. However, ethical decision making and behaviors in more individualistic cultures such as North America, in addition to reciprocal altruism, are influenced by personality factors related to task based efforts, and individualistic values like order, organization, perfectionism, and persistence. By highlighting the role of culture in the relationships among variables, this study shows the necessity of considering the interaction between culture and ethics for having a more accurate picture of the ethical aspect of the human experience.