Zebrafish (Danio rerio) and medaka fish (Oryzias latipes) are popular vertebrate models for various biology fields. Medaka fish have recently attracted attention in the field of social neuroscience due to some of their unique advantages. First, medaka fish females have an extremely short ovarian cycle (24 h), which allows one to obtain a large number of female individuals of a similar physiological status according to their synchronized reproductive rhythms, facilitating quantitative analysis of female behaviors that are strongly influenced by the ovarian cycle; other experimental models such as mice and zebrafish have a longer ovarian cycle and/or unpredictable ovarian maturation. Second, medaka fish possess the visual ability to recognize conspecifics and make appropriate behavioral choices based on their social relationship. Third, the medaka fish are an established model in the field of molecular genetics (as are zebrafish) and state-of-the-art molecular-genetic methods are available. Here we describe several experimental procedures for behavioral paradigms to quantify medaka social behaviors, which are primarily mediated by visual cues.