Background and Objectives: This study demonstrates the factor structure and reliability of the Croatian version of the TOPICOP (Topical Corticosteroid Phobia) questionnaire, thereby contributing to further validation and standardization of the measurement of topical corticophobia with dermatological patients or their parents, which directly affects patient or parent compliance, as well as the final therapeutic effect. Materials and Methods: The cross-sectional, observational study was conducted at the University Hospital Centre Split, Department of Dermatovenerology. The research involved inviting 120 participants (age 12–68) who attended the University Hospital Centre Split’s Atopy School, patients examined in the Dermatology Outpatient Clinic of the University Hospital Centre Split and diagnosed with atopic dermatitis (AD) or allergic contact dermatitis (ACD), and parents or legal representatives of patients younger than 12 years old. The TOPICOP questionnaire consists of 12 items assessing the three different components of topical corticophobia (worries, beliefs, and behaviour). Respondents evaluated their perception of the correctness of each statement within 10 min of filling out the questionnaire on a four-point Likert scale. Results: The response rate was 94%, resulting in a sample of 113 respondents (109 adults and 4 children). Factor analysis yielded one common factor of relatively high reliability (Cronbach α = 0.85, 95% CI 0.81 to 0.89). No differences were found in questionnaire scores between male and female participants, nor between the parents/legal representatives of dermatological patients and other patients. Conclusions: This research contributes to further development of the appropriate measuring instrument, its practical application, and thus, the better recognition, resolution, and prevention of topical corticophobia as part of the better overall healthcare and treatment of chronic dermatological patients.