When decision makers are faced with strategies, there are many factors involved. The Stochastic Dominance gives different viewpoints to the traditional ways, but the applications are subject to its strict rules. As a result,Almost Stochastic Dominance improves the efficiency of judgement, which is able to reveal most investor’s preference. However, our study points out that there is some incorrect result when using ASD rule to define the dominant strategy. In this paper, we establish Conditional Stochastic Dominance (CSD) rule which is more consistent to the financial behavior, and apply CSD rule to analyze the CBOE Buy-Write strategies.