Background: Sexuality is not foreigen to this modern era, including for teenagers. Teen age is very vulnerable to risky sexual behavior. Risk of sexual behavior is influenced by factors of knowledge, understanding of religion, the role of parents, sources of information, and peers. Objective: To analyze the factors that influence risky sexual behavior in adolescents in urban and rural areas. Methods: Non-experimental quantitative with cross sectional design. Research in April 2017 at SMPN 12 Yogyakarta and SMPN 2 Sedayu. A sample of 182 respondents in urban area and 187 respondents in rural area by using simple random sampling technique. Data analysis using Chi-Square test followed by multivariat analysis with Logistic Regression test. Result: Sexual behavior of urban risk is not at risk 124 respondents (68.1%), rural not risk 130 respondents (69.5%). Good urban knowledge 167 ressponden (91.8%), rural good 160 respondents (85.6%). Understanding of urban religion good 161 ressponden (88,5%), rural good 155 responden (82,9%). The role of urban parents is good 171 ressponden (94.0%), good rural 146 respondents (78.1%). Sources of urban information many urban peers good 131 ressponden (72.0%), good rural 132 respondents (70.6%). There was a significant correlation between urban knowledge (p = 0,015) rural (p = 0,031), urban religious understanding (p = 0,032) rural (p = 0,027), rural urban (p = 0,020) rural (p = 0,001) Urban information (p = 0,000) rural (p = 0,000), and urban peer (p = 0,000) rural (p = 0,000). The most influential factor was knowledge of OR = 92.6% in urban and peers OR = 78.2% in rural. Conclusion: The dominant knowledge factor is related to risky urban sexual behavior and the dominant peer factor with risky rural sexual behavior