This study investigates the mentoring function and organizational job outcomes on intention to leave and three measures of career development, psychosocial support and role modeling are related three mediators as job efficiency, job commitment and job performance, The participants are CPAs in Thai accounting firm, using response from 131, and statistic based on Regression Analysis. The results indicate that career development positively influence job efficiency and negatively affect intention to leave, and has no influence on psychosocial and role modeling on job efficiency and job performance. We suggest that the career development is stronger, but psychosocial and role modeling is not significant, managers should train functions of social support and promote modeling in the organization that decreases intention to leave. However, mentoring benefits may be high cost of human resources. The suggestion is more support relationships between mentors and proteges in accounting firms to improve productivity in the long term and reduce employee leave the firm.