The present study aimed at investigating the effect of antecedent congnitive incongruity on reception of information, congnitive curiosity and instigation of information-gathering behavior. One hundred and seven 5th-graders served as Ss. Learning material was classification of animals, using classification of monkeys and apes as an example. The experiment consisted of four sessions: Pre-instruction test was conducted in the first session, presentation of Information 1 and 2 in the second session, Questionnaire I on the consultation and communication after the second session, intermediate test, presentation of Information 3 and post-instruction test in the third session, and followup test and Questionnaire 2 in the fourth session. Different Information 1 was given to experime-. ntal and control groups. Information 1 to experimental group had been constructed to arouse incongruity by informing Ss of the existence of unfamiliar monkeys which were discrepant to the standard of S's conception of a monkey. Information 1 to control group had been concerned with a familiar monkey, so as not to arouse incongruity. The same Information 2 and 3 were given to both groups. Information 2 was designed to reduce latently the incongruity aroused by Information 1 to experimental group and Information 3 to completely and manifestly reduce the incongruity. After each Information was presented, Ss were asked the following two questions:1.“How interesting is this information?” 2.“Would you like to hear more?” They were also required to ask questions in semi and non -forced situations after Information 2. The results were as follows. i) Information received in incongruity-aroused situation was used flexibly in various different situations. Furthermore the Information could be generalized and coordinated. ii) The part of information which had aroused incongruity tended to be retained longer as an interesting part. iii) Information 1 to experimental group, which had more incongruity-arousing components, instigated stronger cognitive curiosity than Information 1 to control group. However, there was no difference in curiosity stimulated by Information 2 and 3 between groups. iv) Experimental group Ss asked more questions, especially incongruity reducing ones, than control group Ss in the semi-forced situation. But there was no difference between groups in the rate of evocation of asking behavior in the non-forced situation.