The present study analyzed demographic and psychological factors that affect adult men's decisions to solicit a prostitute. We administered a questionnaire to 1 400 randomly sampled men aged 20 to 59, who live in the Tokyo metropolitan area (obtaining 664 valid responses). The results revealed that 14.6 percent of respondents have had the experience of being a client in prostitution at some point over the past four to five years. Men in their 50s, who spent their adolescence before the enforcement of anti-prostitution laws, had high prostitution acceptability. Those in their 20s and 30s, who spent their adolescence in the 1990s when “Enjyo-Kousai” (Japanese amateur prostitution)gained topicality, also showed high rates. These findings are considered to be birth cohort effects. In addition, those men who reported grater sexual drive and desire for intimate contact with others, as well as those who reported fewer attitudes of gender egalitarianism, had higher rates of prostitution solicitation. Finally, those men who reported less emotional family bonds also showed higher rates.