Introduction: Social networks are the most widespread form of communication among people today, and social networks influence the creation of both positive and negative self-images. Aim: To examine the influence of social networks on the perception of one's own body in secondary health school students of the teaching program for general nurse general care-general care medical technician in Split and Sinj. Subject and methods: The research was conducted on 234 students of all five classes of the secondary health school of the general care nurse curriculum in Split and three classes of the secondary health school of the general care nurse curriculum in Sinj. The research was conducted from May 15, 2023 to June 19, 2023 through an anonymous questionnaire consisting of a sociodemographic questionnaire, an AAI questionnaire and a questionnaire about social networks. Results: In the research, there are 4.57 times more female respondents than male respondents (p<0.001), while the most common age of respondents is 16 years old (28.21%). The number of respondents who own a computer/laptop is 81.20%. The most frequently used network among respondents is Instagram (55.13%), followed by TikTok (40.60%), while the least used social network is Facebook (2.56%). The largest number of respondents on social networks has between 101 and 200 followers (36.96%). The number of respondents who spend between 3 and 5 hours a day on social networks is 52.61% and the largest number use social networks to correspond with friends (58.52%). The largest number of respondents rarely compare their appearance with the appearance of others on social networks and their number is 5.22 times higher than the representation of respondents who often compare their appearance with the appearance of others on social networks (p<0.001). For 60.43% of respondents, the use of social networks sometimes affects the change of their own previous thinking, while for 2 respondents it always affects (0.87%). Among the respondents, the largest number have never experienced someone insulting them or making negative comments (66.52) and 91.30% of the respondents do not care how many "likes" they have on their social post. Conclusion: The Croatian version of the AAI-questionnaire has satisfactory measurement characteristics for assessing the frequency of cognitive processes and behavioral responses when identifying body dysmorphic disorder in teenagers. The influence of social networks is negatively correlated with a positive perception of one's own body. There is a greater influence of social networks on the perception of one's own body in younger students than in older students. Female students do not report a greater influence of social networks on the perception of their own body than male students. Viewing profiles and pictures of other people is negatively correlated with a positive perception of one's own body. Posting content and pictures about yourself is not positively correlated with the number of likes on posts and positive perception of your own body.