The purpose of the study was to investigate the relationship between high school students' understandings of aspects about nature of science (NOS) and their argumentation skills, particularly whether informed conceptions of NOS contribute to better argumentation skills. Participants, a total of 125 Grade 10 students, responded to an open-ended questionnaire, "Controversial Socioscientific Issues Questionnaire (CSI)," that involved two scenarios addressing socioscientific issues (SSI) about genetically modified food and water fluoridation. Each of the two scenarios was accompanied by two sets of questions that address argumentation and NOS. Stepwise regression analyses were performed on data from the participants' responses with three NOS aspects (subjective, tentative, and empirical) as independent variables and the argumentation components (argument, counterargument, and rebuttal) as dependent variables (each at a time). The results demonstrated positive correlation between argumentation and NOS. Moreover, the results showed that the tentative, empirical, and subjective aspects are significant predictors of the argumentation components with some variations depending on the context (whether genetically modified food or water fluoridation). These results provide concrete evidence illustrating the associations between argumentation and NOS knowledge within two SSI (water fluoridation and genetically modified food).