Research on self-regulated learning ({SRL}) in hypermedia-learning environments is a growing area of interest, and prior knowledge can influence how students interact with these systems. Fifty-two undergraduate students’ interactions with {MetaTutor}, a multiagent, hypermedia-based learning environment, were investigated, including how prior knowledge affected their use of {SRL} strategies. We expected that students with high prior knowledge would engage in significantly more cognitive and metacognitive {SRL} strategies, engage in different sequences of {SRL} strategies, spend more time engaging in {SRL} processes, and visit more pages that were relevant to their sub-goals than students with low prior knowledge. Results showed significant differences in the total use of {SRL} strategies between prior knowledge groups, and more specifically, revealed significant differences in the total use of metacognitive strategies, but not total cognitive strategies between prior knowledge groups. Results also revealed different sequences of use of {SRL} strategies between prior knowledge groups, and that students spent different amounts of time engaging in {SRL} processes; however, all students visited similar numbers of relevant pages. These results have important implications on designing multiagent, hypermedia environments; we can design pedagogical agents that adapt to students’ learning needs, based on their prior knowledge levels.