Researchers state that adolescents are likely to engage in risky photo disclosure online, which might be related to their emotions and personal characteristics. Research Questions: How positive and negative emotions when sharing risky photos online are related to adolescents' risky photo disclosure online? How important personal characteristics are related to adolescents' risky photo disclosure online? The purpose of this study is to find out how positive and negative emotions are related to adolescents' tendency to engage in risky photo disclosure and how personal characteristics (narcissism, social anxiety and privacy concern) are related to such kind of behaviour. A randomised cross-sectional survey with a hardcopy questionnaire, based on the measures of variety of the forms of risky photo disclosure online (e.g., sharing nude photos); frequency of risky photo disclosure when feeling positive and negative emotions; personal characteristics (social anxiety, narcissism and privacy concern) was conducted in 2019. 459 adolescents (59.1% female) aged 12-17 years old (M=14.55, SD=1.24) participated in the study. The results of the study showed that positive and negative emotions towards sharing risky photos on risky photo disclosure online (F=136.85, p<.001) explains 56% of actual adolescents' risky photo disclosure, with the strongest predictor of positive emotions (β=0.82, p˂α); personal characteristics (F=8.57, p˂α) explain only 9.6% of risky photo disclosure online, with the strongest predictor of narcissism (β=0.25, p˂α). According to the results, we conclude that positive emotions towards sharing risky photos online and more expressed narcissistic personality trait increases adolescents' tendency to engage in risky photo disclosure online.