The experience of awe, an emotional response to vast stimuli overwhelming ones’ current mental structure, has often been measured using a questionnaire method. The purpose of the present study was to develop and validate the Japanese version of the Situational Awe Scale (SAS), which is a useful tool for measuring awe experiences from the perspective of the discriminability between positive- and threat-awe. The present study investigated the factor structure and validity of the Japanese version of the SAS (SAS-J) using awe-inducing video clips, through three online surveys (N = 1034; mean age = 38.74, SD = 10.95, range = 18–75). Results revealed that the SAS-J consisted of the same four factors as the original SAS (i.e., connection, oppression, chills, and diminished self) and had the convergent, criterion, and discriminative validity in measuring both positive- and threat-awe experiences. Additionally, results showed that the SAS-J could distinguish between positive- and threat-awe experiences. These results suggested that the SAS-J could measure both positive- and threat-awe experiences with validity. This study would make a methodological contribution to awe research.