The purpose of this study was to investigate the difference of science-related background and experience between two groups of elementary teachers: one with high personal self-efficacy about science teaching and the other with low personal self-efficacy. The qualitative research method was employed to collect and analyze data. In order to identify elementary teachers who have high and low personal self-efficacy about science teaching, an instrument of self-efficacy beliefs about science teaching was administered to 250 elementary inservice teachers. Ten teachers out of 250 were selected and divided into two groups for this study: five for high personal science teaching self-efficacy and another five for low self-efficacy. These ten teachers were all participated in interview qualitative research. The major findings are: 1) All five teachers of high personal self-efficacy have positive experience of science which positively influenced their self-efficacy beliefs about science teaching. 2) On the other hand, all five teachers of low personal self-efficacy have negative experience and perception of science which negatively influenced their science teaching self-efficacy beliefs. These findings provide a niche for newly developing and implementing teachers training program in a way that elementary inservice teachers could have positive experience and ultimately have high self-efficacy beliefs about science teaching during the course of their teacher preparation.