Introduction: Sleep-related cognitive and behavioral characteristics play an important role in the maintenance of insomnia. Culture affects individuals’ belief system and behaviors, but few studies have examined how Chinese subjects describe their experiences of insomnia and how they deal with it. This study explored the topic using qualitative and quantitative approaches. Methods: Participants were recruited from the community via advertisements. Their DSMIV diagnosis of primary insomnia for at least 6 months was confirmed by a sleep specialist with the help of the Structured Clinical Interview for DSM-IV and sleep-wake questionnaires. A focus group approach was used to elicit participants’ insomnia experiences. They were also asked to keep a 1-week insomnia experience diary prior to attending the focus group and to complete a set of sleepwake questionnaires, including the 30-item Dysfunctional Beliefs and Attitudes about Sleep Scale after the group meeting. Each focus group comprised 6 to 8 participants. Discussion was led by a facilitator with a pre-determined question route and it was audiotaped, transcribed verbatim, and managed with NVivo software to facilitate coding and analysis. Focus group data collection ceased when data saturation was achieved. All data were fragmented into meaningful units, compared iteratively, and assigned with descriptive codes to condense the emerging meanings. Codes pertaining to the same phenomena were grouped together and a coding framework was built. The findings from the qualitative study were then validated in a quantitative questionnaire survey of a separate group of participants with chronic primary insomnia and good sleepers. Results: A total of 6 focus groups were arranged, involving 31 women and 12 men, with an average age of 51 years. Participants had a mean duration of insomnia of 11.81 years, and an average sleep-diary derived sleep efficiency of 70.57%. There were 16 sub-categories and 4 categories of characteristics. The 16 sub-categories could be grouped under: 1) beliefs regarding the nature and treatment of insomnia, 2) behavioral responses to insomnia, 3) cognitive-emotional and physiological arousal, and 4) emotional experiences associated with insomnia. Significant difference between primary insomniacs and good sleepers was found on 9 out of 14 items of the quantitative scale we developed based on the qualitative study results. Seven items remained significant after Bonferroni correction (p < .003), including 1) puzzlement about cause, 2) realistic sleep expectation, 3) constant search for treatment, 4) nighttime negative emotions and physiological symptoms, 5) heightened vigilance, 6) association of sleep with suffering, and 7) sleep problem not understood by others. Conclusion: The present study serves as the first to use both qualitative and quantitative approaches to identify the subjective experience of Hong Kong Chinese insomnia patients. Questionnaire study confirmed that the identified experience was also found in a separate chronic insomnia sample. It sheds light on tailoring CBT-I for the local population with chronic insomnia. Further research on the efficacy and acceptance of a tailor-made local CBT-I program is needed. / published_or_final_version / Psychiatry / Master / Master of Philosophy