The paper reports a qualitative study to reveal how preservice science teachers' decision making (DM) processes on socioscientific issue (SSI) in a referendum case compare between unsophisticated (Group U) and sophisticated (Group S) views in terms of nature of science (NOS) understandings. Firstly, pre-study was conducted with focus group interviews with pre-service science teachers. With the findings, one-on-one semi-structured in-depth interviews of the main study for DM on SSI, the artificial meat was developed. In the main study, 12 participants' responses were analyzed, and a new DM model named the Fractal Model of DM which reflects real-life situation DM process, especially referendum case, was constructed. In DM, NOS lens usages of five NOS aspects about creativity and imagination, observation and inference, empirical-basis, subjectivity, and social and cultural embeddedness and 23 other lens usages such as animal rights (morality), economic, and risk factor were detected and explained through the fractal model. Findings showed that there is a hidden and complex effect of NOS understandings about tentativeness of scientific knowledge on DM. With multiple lens usage, each participant had multi-perspective considerations in DM. While Group S used NOS lenses mainly parallel with their NOS understandings, Group U used them in a more complicated way.