Background: Indoor tanning is a common adolescent risk behavior that has been hypothesized to be motivated and maintained by the mood-altering effects of ultraviolet light. Objective: Our purpose was to explore heretofore anecdotal reports that indoor tanning leads to dependency. Methods: A telephone interview was conducted among 1275 adolescents, ages 14 to 17 years. Self-reported difficulty in quitting indoor tanning was assessed among 267 adolescents (20.9% of total) who tanned indoors more than once in the previous year in relation to age of initiation, frequency of use, and positive or negative consequences of the practice. Results: Difficulty in quitting was more likely with younger age at initiation (age 13 years or younger vs ages 16 to 17; odds ratio = 4.3, 95% confidence interval 1.3-14.7) and higher frequency of use (P = .009), even after accounting for positive or negative consequences of indoor tanning and other demographic characteristics. Limitations: This was a cross-sectional study design with a limited outcome measure. Conclusion: Although preliminary, our findings for age at initiation and frequency of use in relation to difficulty in quitting indoor tanning are consistent with other potentially addictive behaviors taken up during adolescence.