The purpose of this study is to analyze changes in EEG activation that occur when performing the inductive inquiry tasks and the deductive inquiry tasks. EEG measurement tasks were developed which were divided into criteria tasks and scientific inquiry tasks. The scientific inquiry tasks were developed by dividing them into the inductive inquiry tasks and the deductive inquiry tasks. EEG data were collected from 12 university students in Busan. Relative power spectrum activity difference analysis and the sLORETA analysis method was performed from the collected EEG data. The results of the study are as follows. First, the theta band showed relatively higher activation in the frontal lobe and the parietal lobe when performing the inductive inquiry task than when performing the deductive inquiry task. The alpha band showed relatively higher activity in the frontal lobe, the parietal lobe, and the temporal lobe when performing deductive inquiry tasks than when performing inductive inquiry tasks. In addition, the beta band and the gamma band showed relatively higher activity in the frontal and parietal lobes when performing deductive inquiry tasks than when performing inductive inquiry tasks. Second, as a result of the sLORETA analysis, when performing the deductive inquiry task compared to the inductive inquiry task, higher activity was found in the precentral gyrus and the middle frontal gyrus. These results show that inductive and deductive thinking have different cognitive characteristics in terms of planning and performing task solving, comparing information on targets and target elements, selecting appropriate information, goal-oriented attention, selective memory retention and forgetfulness, spatial information recognition of targets, and visual working memory. Through this, we propose a neurophysiological basis for the validity of cognitive psychological explanations for inductive and deductive exploration and the possibility of follow-up studies in various aspects.