By using empirical data, this paper investigates the processing mechanism of moral intensity’s effects on organizational employees’ ethical decision making, under different ethical climates’ moderation. The findings suggest that three dimensions of moral intensity all have direct effects on three stages of ethical decision making behavior, and different kinds of ethical climates play different kinds of moderating roles in the positive relationship between moral intensity and ethical behavioral intention. By analyzing the external factors’ mechanism on the processing mechanism inside ethical decision making, this paper makes the mechanism underlying the ethical decision making system more clear, and helps the enterprise to improve employees’ ethical decision making level via taking appropriate measures.