Purpose: This study investigated the smartphone using time, troubles with smartphone usage, and related factors in Korean adolescent smartphone users. Methods: Data were obtained from 54,603 subjects aged 13 to 18 years in the 2017 13th Korea Youth Risk Behavior Web-based Survey Results: The study analyzed the school type, academic achievement, residence type, weekly average allowance, and usual counselor, perceived stress, happiness, and depression of the subjects showed a significant difference in the variable of troubles experienced by the smartphone user. Multiple sample logistic regression analysis showed that adolescents with low academic achievement (weekday, weekend OR = 1.78, 1.65), low economic status (weekday, weekend OR = 1.17, 1.37), friends with distress counselors (weekday, weekend OR = 1.29, 1.24), weekly average allowance (weekday, weekend OR = 1.85, 1.50), stressed (weekend OR = 1.25), depressed (weekday, weekend OR = 1.26, 1.14), family troubles (weekday, weekend OR = 1.14, 1.15), friendship troubles (weekday, weekend OR = 1.70, 1.38), and academic performance troubles (weekday, weekend OR = 1.28, 1.38) spent more than the average using time on their smartphones. Conclusion: To prevent overdependence on smartphone use among adolescents, a nursing intervention program that relieves stress and lowers depression should be developed.