Dog personality scales are used to assess the behavioral traits of dogs working in various situations. The purpose of this study was to develop a Japanese version of the Dog Personality Scale (JDPS) of Kubinyi et al. (2009), in order to serve the small-dog-oriented society of Japan. In Study 1, we conducted a pilot survey and factor analysis was performed on the collected data. As a result, four factors were extracted: “Calmness,” “Dog sociability,” “Boldness,” and “Trainability,” which were similar to those in the scale developed by Kubiny. Moreover, we confirmed the reliability of JDPS (Cronbach's alpha = 0.69–0.79). In Study 2, the concurrent validity of the JDPS was confirmed by examining the relationship between the JDPS and the Problem Behavior Checklist (|r| = 0.02–0.55), as well as evaluations by dog owners and dog instructors (r = 0.65–0.88). In Study 3, the predictive validity of the scale was partially confirmed by examining the relationship between JDPS scores and actual behavior of the dogs (Calmness: r = 0.42; Trainability: r = 0.36). The newly developed JDPS has good reliability and validity and can easily be used to assess the behavioral traits of dogs in Japan.