From the study of the factors affecting the ethical climate at work and the roles of human resources practices in reinforcing employee’s ethical climate and fair treatment, the primary data were derived from questionnaire of the survey research. The population was employees who had been working in private sectors. Total sample size was equal to 1,215. The factors affecting ethical work climate were categorized into 4 groups: individual factors, work-related factors, organizational factors and other environmental factors. The results revealed that the perception of ethical work climate were influenced by in-work positions, tenure, characteristics of supervisors, and levels of business competition at the significant level of 0.05. For the roles of human resource practices promoting ethical work climate; ethical-related training courses, performance feedback and levels of payment affected the perception of ethical climate at the statistically significant level of 0.05. The study, therefore, proposed ethical reinforcement at work by focusing on the mentioned factors of human resource practices on ethical work climate.