In a sample of 157 Norwegian political science undergraduates, two dimensions of epistemological beliefs concerning Internet-based knowledge and knowing were identified through factor analysis. The first dimension, general Internet epistemology, ranged from the integrated view that the Internet is an essential source of true, specific facts to doubt about the Internet as a good source of true, factual knowledge. The other dimension, justification for knowing, ranged from the view that Internet-based knowledge claims can be accepted without critical evaluation to the view that knowledge claims encountered on the Internet should be checked against other sources, reason, and prior knowledge. Further, it was found that students' personal epistemology concerning Internet-based knowledge and knowing predicted their self-reports of Internet-search and -communication activities in better and more consistent ways than did Internet self-efficacy beliefs.