Socioscientific issues (SSI) related teaching may positively influence students' scientific epistemological beliefs (SEB). However, research is limited about elementary school students and the methods of web search. This study aimed to investigate Taiwanese sixth-graders' SEB and the impact of different web searches' information positions (positive, negative, conflicting) for the SSI on their SEB. Two SSIs (smartphone use by elementary school students and continued construction of the nuclear power plant) were designed and placed in the closed-end search platform with three information positions. This study investigated the participants' overall and four dimensions (source, justification, certainty, and development) of SEB before and after web searches. Results showed that their initial SEB tended slightly toward constructivism, but there is a need for improvement in the source and certainty dimensions. Regardless of the information position groups, the SSI-focused web searches moved the tendency of source dimension and overall SEB more toward constructivism. The web search of the conflicting group enhanced most dimensions of SEB, while the negative group had a larger effect size of overall scores and dimensions of source and justification. Accordingly, this study provides suggestions on applying different information positions of SSI-focused web searches to improve students' SEB in different dimensions.