<p>The purpose of this study was to examine the relationship between sexuality education for elementary schoolchildren at home and their guardians' parenting factors, and to identify promoting and inhibiting factors in sexuality education by guardians at home.</p><p>Two surveys were carried out. In the first survey, semi-structured interviews were conducted with 4 Yogo teachers and 15 mothers of elementary schoolchildren to examine the factors affecting sexuality education at home. The results revealed some important factors, e.g. “realization of the significance of sexuality education by guardians", “a sense of crises about sexual health risks" and “lack of qualities for sexuality education". Based on the results, the questionnaire for the second survey was developed.</p><p>In the second survey, self-administered questionnaires were distributed to guardians (n=686) of 6^th grade elementary schoolchildren in Sapporo-city. From 448 mothers' answers, factor analyses of responses yielded 12 factors related to sexuality education. Simple and multiple regression analyses showed that “lack of qualities for sexuality education" was related significantly with “experiences of teaching sexuality education", “anxiety about children's negative response" and “a sense of crises about sexual health risks", and that “experiences of teaching sexuality education" was related significantly with “realization of the significance of sexuality education at home" and “respect for dialogue between parents and children". Results of path analyses indicated that “self-confidence of future sexuality education"was promoted by “experiences of teaching sexuality education" and was inhibited by “lack of qualities". These findings also suggest that guardians need to realize the significance of sexuality education, to enhance the communication between parents and children, and to remove the anxiety about sexuality education.</p>