The aim of the present paper is to examine the risks and benefits of employing evidence in school safety education in Japan. In the past, evidence was typically not utilized in school safety (absence of evidence). Even when evidence is utilized, there are cases where measures are promoted based on misinterpreted numerical values (risks of evidence). It is important that evidence be adopted cautiously based on scientific procedures, and that is how substantial safety is attained (benefits of evidence). [This article was originally published, in Japanese, in "The Japanese Journal of Educational Research" Vol. 82, No.2, 2015. Translated by Ai Ohmori.]