The aim of this study was investigated the relationship between preservice science teachers' 21st century learner and teacher skills and their science learning self-efficacy beliefs. The research method used was the correlational research method, one of the quantitative research methods. The sample of the study was consisting of 318 preservice science teachers studying in the third and fourth grades of the science education department of the education faculties at three public universities. Data collection tools of this study were the 21st Century Learner Skills Scale, the 21st Century Teacher Skills Scale and the Science Learning Self-Efficacy Questionnaire. The data obtained were analyzed by structural equation modeling (SEM). In the results obtained from the SEM1, SEM2 and SEM3, a correlation was determined between the preservice science teachers' 21st century teacher skills, 21st century learner skills and science learning self-efficacy beliefs. In addition, the preservice science teachers' science learning self-efficacy beliefs positively correlated with their 21st century learner skills and negatively correlated with their 21st century teacher skills while their 21st century learner skills positively correlated with their 21st century learner skills. The preservice science teachers' 21st century skills and science learning self-efficacy beliefs was found to be predicting each other. Studies to identify the relationship between different dimensions of science education and 21st century skills should be performed to contribute to the relevant literature.