Introduction: Nomophobia is characterized by intense fear or anxiety resulting from being without access to a mobile phone, potentially impacting mental health and behavior.
Objective: This study aimed to model nomophobia in high school students based on the quality of the parent–child relationship and attachment styles, with loneliness as a mediating variable.
Method: The study used a descriptive-correlational design with structural equation modeling. The population consisted of all female and male students in the second level of high school in Khorramabad during 2022–2023. Using cluster random sampling, 299 students were selected and completed the Nomophobia Questionnaire, Parent–Child Relationship Questionnaire, Attachment Styles Questionnaire, and the UCLA Loneliness Scale. Data were analyzed using SmartPLS version 3.
Results: Findings revealed that the quality of the parent–child relationship had an indirect effect on nomophobia through loneliness (β = 0.481, p < 0.01). Similarly, attachment styles indirectly affected nomophobia via loneliness (β = 0.481, p < 0.01). Both the parent–child relationship (β = 0.163, p < 0.01) and attachment styles (β = 0.328, p < 0.01) had direct effects on nomophobia.
Conclusion: Improving the parent–child relationship, educating students and parents about attachment styles, and addressing loneliness may help reduce nomophobia among adolescents