Purpose: The aim of this study was to investigate the occlusion, the demand for orthodontic treatment and the reasons for this among Chinese young adults in Hong Kong. Materials and Methods: A questionnaire was used to study previous orthodontic experience and to evaluate the orthodontic treatment demand and the reasons for this in Chinese university students. Among those who had no orthodontic treatment, 120 participants were invited for an occlusal assessment. Their treatment need was graded using the index of orthodontic treatment need. Results: A total of 240 students, aged 18 to 27 years, completed the questionnaire survey. Thirty-one students (13%) had orthodontic treatment. Sixty-seven (28%) students had orthodontic treatment demand, and their common reasons were to improve appearance (78%), self-image (36%), self-confidence (34%) as well as to follow parental advice (24%). The reasons for those students who would not consider having orthodontic treatment included no perceived need (64%), long treatment time (18%) and high treatment fee (14%). All 120 invited participants who had no orthodontic treatment attended the occlusal assessment. One-fifth had a normal occlusion. Most malocclusions were manifested as Angle Class I (48%) followed by Class III (21%) malocclusion. Fifty-six students (47%) had moderate and 40 students (33%) had 'great' or 'extremely great' treatment need. Conclusions: The most prevalent malocclusion among this group of Chinese young adults was Angle Class I malocclusion. Although the majority of the Chinese young adults had malocclusion with a high treatment need, their demand for orthodontic treatment was relatively low. Apart from consideration of dental health needs, the common reasons for orthodontic treatment demand were influenced by the desire for improvement in appearance. Keywords: adult, occlusion, orthodontic, treatment demand