The paper reports about an empirical study investigating the relationship between scientific epistemological beliefs, intellectual risk-taking in science learning and science achievement of middle school students via path analysis. The sample was composed of 2119 middle school students enrolled in public schools. Nearly half of the students (50.9%) were female. 'Personal Information Form', 'Scientific Epistemological Beliefs Scale', 'Intellectual Risk-Taking Scale' and 'Science Achievement Test' were used in data collection. During the data analysis of the relationship between scientific epistemological beliefs, intellectual risk-taking and science achievement, Path diagrams and analysis were used. Results of the analyses showed that 'certainty', 'improvement' and 'verification' aspects of scientific epistemological beliefs positively predicted science achievement while the 'source' aspect predicted negatively science achievement. Furthermore, scientific epistemological beliefs predicted significantly intellectual risk-taking. Moreover, it was found that intellectual risk-taking levels of the students positively predicted achievements in science. In conclusion, it was seen that there was a causal relationship between scientific epistemological beliefs, intellectual risk-taking and science achievement of middle school students.