The purpose of this study was to investigate a motivation system about science learning and interest in science among elementary, middle & high school students and analyze on the their relations. For this, the questionnaires on interest in science that developed by Kind et al., (2007) were selected and translated. After that, second-grade 80 students, fourth-grade 87 students, sixth-grade 107 students, eighth-grade 123 students and eleventh-grade 128 students were required to accomplish a questionnaire on behavioral inhibition system/behavioral activation system about science learning (SL-BIS/BAS), interest in science. Based on these materials, SL-BIS/BAS by student's variables and relations of between the system to interest in science have been analyzed. The result of this study shows the followings. First, the sensitivity about SL-BIS was no significant difference in School levels. But sensitivity about SL-BAS and interest in science in elementary and high school was higher than it in middle school. Second, there were low negative correlation with SL-BIS and interest in science, and relatively high positive correlation with SL-BAS and interest in science. Through the results of this study, relations of motivation to related variables, and the motivation by student's variables are identified. These results would be helpful for teachers to understand the difference about motivation by students' variables and to make a plan for the appropriate strategies for learners.