Background The most challenging task in eye-tracking-based multimedia research is to establish a relationship between eye-tracking metrics (or cognitive processes) and learners' performance scores. Additionally, there are current debates about the effectiveness of animations (or simulations) in promoting learning in multimedia settings. Objectives As a result, the current study aimed to review eye tracking-based research on learners' cognitive processes in the animated/simulated multimedia learning domain. Method For this purpose, fifty-seven (57) studies were systematically determined based on PRISMA guidelines, and they were synthesized. Results and Conclusions The notable findings are that (1) most of the reviewed studies have tried to relate eye-tracking measures to at least one cognitive process (e.g., selecting, organizing, and integrating) which are assumed to take place during multimedia learning; (2) eye-tracking measurements show whether design features of animation are successful in directing learners' attention; (3) the success of animation in attention-guiding to the relevant parts may not have a positive impact on learning because individual differences (e.g., prior knowledge, spatial ability, or working capacity) and animation content are the other factors that directly affect the effectiveness of animation over learning. Implications The current study implies that (i) use of signaling cues in animated multimedia settings diminish visual search and promote higher learning scores, (ii) giving users control over animations causes negative outcomes (e.g., missing micro or macro events); (iii) research on animated multimedia learning should be replicated with the participant group from K-12, special education (e.g., autistic children), and elders.