Electronic Dictionary (ED) was one of the most popular learning tools with its increasingly diversified design ranging from information searching to knowledge management. Although previous research has surveyed in terms of the relation between ED and learning outcomes, few studies employed objective measurements, such as biofeedback, along with a qualitative approach to investigate learners' using behaviors and their cognitive process. The current study proposed to capture participants' three eye movement dates including fixation counts, fixation duration and scanning path, which were utilized as the stimulus to help participants to retrospect their cognitive features. The fixation interestingly shows that the areas of interest are somewhat impaired with their expectation in presurvey, for example, users claimed they prefer as many as example sentences, while only the first three were noticed. Moreover, the scanning paths frequently moved back and forth among some elements, which indicate learners tried to make connections among some specific elements to help enhance learning efficiency. The stimulated recall interview was employed to further explore their cognitive process based on their eye movement data, and some implications were made for the optimization of the ED design to meet learners' personalized requirements.