Objective: To compare sleep quality and emotional/behavioral problems among asthmatic and non-asthmatic children with or without moderate to severe obstructive sleep apnea. Method: An AHI-range-matched BMI-range-matched cross-sectional design was used to examine polysomnographic evaluation and emotional/behavioral problems in 102 non-obese children aged between 6 and 12 years old, categorized as with or without asthma and sleep disordered breathing. Results: Asthmatic children in AHI ? 5/h group revealed a significantly longer sleep latency, a greater leg movement index (LMI), and a lower ratio of slow wave sleep compared with non-asthmatic AHI ? 5/h group. Compared with non-asthmatic AHI > 5/h group, asthmatic children displayed a higher ratio of REM sleep, sleep stage 1 and 2, a lower ratio of slow wave sleep, as well as a greater respiratory arousal index and LMI. There was no significant difference in emotional/behavior problems among groups. Conclusion: Sleep disturbance exists in asthmatic children with or without moderate to severe obstructive sleep apnea. Non-obese asthmatic children had less slow wave sleep compared with non-asthmatic children. We might recommend that sleep quality could be noticed and evaluated in children with asthma. ? 2014 Elsevier B.V.