The aim of this study was to determine the effect of flipped classroom model on fifth grade students' 21st century skills and scientific epistemological beliefs. The sample of the study was consisted of 54 fifth grade students from a rural elementary school in Turkey. Quasi-experimental design with pre-test and posttest control group was used. As a data collection tool, "Scientific Epistemological Beliefs Scale" and "21st Century Learning Skills Scale" was used. For data analysis, independent t-test and dependent t-test were used. As a result of the study it was found that; at the beginning, there was no significant difference between the experimental and control group students' pre-test scientific epistemological beliefs. After the implementation, there was no significant difference between the experimental and control group students' posttest scientific epistemological beliefs mean scores. In addition, at the beginning of the study, there was no significant difference was found between experimental and control group students' 21st century skills. After the implementation, there was no significant difference was found between experimental and control group students' 21st century skills after the implementation.