This research, which aims to investigate high school students' nomophobia perceptions and these perceptions according to personal variables, is in a quantitative and screening model. In November and December 2022, data were collected by reaching 806 students from the students studying at official high schools in the central districts of Denizli, using an easily accessible method. As a data collection tool, 20 items and a 4-dimensional nomophobia scale were used. Regarding the nomophobia perceptions of high school students, it is seen that they experience mild and moderate nomophobia on the basis of items, while the highest level of nomophobia perception is "I am worried that my family and/or friends cannot reach me." It is in the article. The lowest level of nomophobia perception is “I feel uneasy because I cannot check my e-mails.” It is in the article. High school students' nomophobia levels are at the highest level of not being able to communicate, followed by the dimensions of not being able to access information and giving up comfort. The lowest nomophobia level is mild in terms of fear of losing online connection. General nomophobia levels were measured at a moderate level. It was observed that high school students' nomophobia perceptions did not differ according to school type and were similar. It has been determined that girls have higher nomophobia perceptions in all dimensions and in general, according to their genders. In the dimension of waiving comfort for age, it was high in favor of the younger ones, while it was low against the 12th grade students, sacrificing comfort according to grade levels, inability to communicate and generally. According to the number of social networks they use and the time spent on the phone daily, it has been observed that the nomophobia levels are higher in all dimensions and in favor of those who have more networks and spend more time on the phone daily.