Global HIV-1 epidemic has evolved into a human security issue rather than one of the health problems, particularly in sub-Saharan Africa. HIV-1 epidemic is also growing in Asia, being projected to soon explode in the world largest countries, India and China. Japan is at stake of future epidemic, because of the possible influence of the epidemic in neighboring countries and more because unprotected sex is clearly prevailing among Japanese youth. This is reflected in the sudden and synchronized increase in STD and induced abortion among teenagers and endorsed by the recent nationwide sexual behavior surveys that showed sexual behavior of the youth being highly networked and unprotected. Prevention programs should be soon developed and implemented in Japan.