This study aims to investigate the relationship between chronotype preferences/sleep problems and trauma symptoms during the COVID-19 outbreak of adolescents diagnosed with Anxiety Disorder (AD) in the pre-COVID-19 period. The sample of this study consisted of 71 adolescents with AD. Trauma symptoms were evaluated using the Children’s Event Impact Scale (CRIES-13); sleep habits were assessed using the Pittsburgh Sleep Quality Index (PSQI); and chronotype was evaluated using the Children’s Chronotype Questionnaire (CCQ). The CRIES-13 arousal scores and PSQI sleep latency scores were significantly higher in the eveningness type group compared with the non-eveningness type group. The CRIES-13 arousal scores of adolescents with AD were related to the CCQ and PSQI scores. In linear regression analysis, sleep problems were found to be an associated factor on the CRIES-13 scores. The findings of the present study suggest that during the COVID-19 pandemic, the chronotype may play an important role in the adversities experienced by adolescents with AD. In addition, it was thought that the association between sleep problems and trauma in adolescents with AD who spent a lot of time in the home environment during the pandemic period needs further evaluation.