With the perspective of new institutionalism, taking rational-economic man as the supposition and institutional actor as the role for judges, the behavior of judges can be well explained in the real world. In the local institutional context of China, we can construct the “utility function” for Chinese judges' behavior. In this utility function, the risk of being punished for misjudged cases and the performance assessments constitute the basic variables that may affect the judge's utility. For the utility-oriented institutional incentives, the judge may make the strategy to seek advantages and avoid disadvantages, resulting in the deviation of judicial decisions. Therefore, it is necessary to strengthen judicial reasoning, optimize judicial decision environment, and establish correct institutional incentives, so as to control the behavior deviation of judge's decision-making.