This study examined the impact of integrating virtual science inquiry activities with Predict-Observe-Explain (POE) teaching strategies on 5th graders' understanding of science concepts and epistemic beliefs in science. A cohort of 80 5th graders (mean age of 12 years old, 40 boys and 40 girls) from a public primary school in North China took part in the research. The data collected encompassed pre-test and post-test results on understanding of science concepts and epistemic beliefs, along with students' behavioral data during virtual science inquiry. The findings demonstrated that integrating virtual science inquiry activities with POE strategies increased students' understanding of science concepts and epistemic beliefs in science. Furthermore, notable differences were found in observation time and inquiry strategy between high and low achievers, while significant distinctions in page time allocation and page navigation behavior were evident between boys and girls. The results provided empirical support for enhancing the implementation of virtual science inquiry activities in primary school science learning.