Background: Ethical leadership represents the leader's proactive efforts to influence followers' ethical and unethical behavior and Follower work attitudes such as perceived organizational support, affective commitment and normal behaviors. The purpose of this research was to test the relationship of ethical leadership and ethical context with affective commitment that mediating the role of perceived organizational support.

Method: The method of current study was descriptive-correlation. Population of this research includes all of the employees of Karun Oil and Gas Producing Company. The sample consists of 300 employees of KOGPC who were selected by stratified random sampling method. The instruments which used in this study were Ethical Leadership Questionnaire (10 items), Ethical Context Scale (5 items), Perceived Organizational Support Survey (8 items) and affective commitment Scale (8 items). Fitness of the proposed model was examined through structural equation modeling (SEM), using SPSS-19 and AMOS-18 software packages. The indirect effects were tested using the bootstrap procedure.

Results: Results indicated that ethical leadership and ethical context both directly and indirectly through the mediation of perceived organizational support had a relationship with affective commitment.

Conclusion: According to these results perception of ethical leadership and ethical context through perceived organizational support can affect mainly on employee’s positive work attitudes such as affective commitment, job motivation and productive behaviors. We expect ethical leadership to be related to positive follower attitudes because of ethical leaders' honesty, trustworthiness, caring and concern for employees and other people, and their fair and principled decision-making.