Diabetes among working population brings to society concerns on productivity and social welfare cost, in addition to healthcare burden. While lower socio-economic status has been recognised as a risk factor of diabetes; occupation, compared with other socio-economic status indicators (e.g., education and income), has received less attention. There is some evidence from studies conducted in Europe that occupation is associated with diabetes risk, but less is known in Asia, which has different organisational cultures and management styles from the West. This study examines the association between occupation and diabetes risk in a developed Asian setting, which is experiencing an increasing number of young onset of diabetes and aging working population at the same time. This is a cross-sectional study of working population aged up to 65 with data from a population-based survey collecting demographic, socio-economic, behavioural and metabolic data from Hong Kong residents, through both self-administered questionnaires and clinical health examinations (1,429 participants). Non-skilled occupation was found to be an independent risk factor for diabetes, with an odds ratio (OR) of 3.38 (p < 0.001) and adjusted OR of 2.59 (p = 0.022) after adjusting for demographic, behavioural and metabolic risk factors. Older age (adjusted OR = 1.08, p < 0.001), higher body mass index (adjusted OR = 1.23, p < 0.001) and having hypertriglyceridemia (adjusted OR = 1.93, p = 0.033) were also independently associated with diabetes. Non-skilled workers were disproportionately affected by diabetes with the highest age-standardized prevalence (6.3%) among all occupation groups (4.9%-5.0%). This study provides evidence that nonskilled occupation is an independent diabetes risk factor in a developed Asian setting. Health education on improving lifestyle practices and diabetes screening should prioritise non-skilled workers, in particular through company-based and sector-based diabetes screening programmes.