Study objectives: To examine the relationship between pre-sleep cognitions and sleep-onset difficulties in an adolescent sample. Methods: Participants comprised 385 students (59% male) from grades 9 to 11, aged between 13 and 18 years (M = 15.6, SD = 1.0), from eight co-educational high schools of varied socio-economic status in metropolitan Adelaide, South Australia. The cross-sectional study used a questionnaire battery including the Sleep Anticipatory Anxiety Questionnaire -Adolescent Version (SAAQ-A), completed during school time, followed by eight days of sleep diary completion and wearing wrist actigraphy to obtain subjective and objective sleep onset latency (SOL). Results: Significant relationships were found between somatic arousal (SAAQ-A subscale) and objective SOL and also between sleep-related cognitions (SAAQ-A subscale) and subjective SOL and SOL overestimation (sleep misperception). No relationships were found between subjective SOL and somatic or rehearsal and planning cognitions. Objective SOL was not related to rehearsal and planning and to sleep-related cognition scores, and sleep misperception had no relationship with somatic as well as rehearsal and planning cognition scores. Conclusions: These findings are not only similar to those in clinical adult populations but also notably different, for example, the lack of association between negative sleep-related pre-sleep cognitions and objective sleep difficulty. The results of this study provide a basis for a more detailed causal study on the existing relationships between negative pre-sleep cognitions and subjective and objective sleep difficulties in this population.