Recently, most researchers have been toward a concern for the cognitive processes underlying decision making because of the development of cognitive psychology. According to information processing theory, process tracing approaches such as information board method was adopted to explore decision-makers´ decision behavior under choice situation. Therefore, the purposes of the study are: (1) to explore the amount of information-used by decision makers in choice process; (2) to analyze decision makers´ searching patterns and the variability of search in choice process; (3) to analyze decision makers how to use decision rules as well as the relation between rules-used and the factors that influence rules-used. The hypothesis was tested in a 3(subscript *)3(subscript *)2 factorial design laboratory study. Subjects were 180 teacher college´s students. "Assessment of Career Decision-making Questionnaire" was used to select three types of decision makers from 300 college students. The number of attributes and information display formats were demonstrated in the experiment. The results were as follow: (1)The three factors-decision style, the number of attributes and display formats had no interaction effects on decision behavior. (2) Dependent decision makers used much more information and searched information repeatedly than intuitive ones. As the number of attributes per alternative increased, subjects searched less amount of information. Under the condition of standard matrix format, decision makers used much more information and used information repeatedly. (3) Rational and dependent decision makers used interdimensional searching pattern in decision process. As the number of attributes increased, most decision makers searched information interdimensionally and the variability of search increased. And different display formats resulted in different searching patterns. (4) The result revealed that compensatory strategies-AL and AD rules were the dominant mode used by decision makers. The rule-used was related to decision styles and the number of attributes. The study indicated that decision behavior was affected by decision styles, the number of attributes and display formats, even though the contingent processing hypothesis was not supported.