Diabetes mellitus is a significant global health concern that is projected to affect 7.7% of the global population by 2030. Understanding factors that influence diabetes knowledge and management adherence is crucial for effective diabetes mellitus management and prevention. This study investigates the relationships between demographic and clinical factors and their impact on diabetes knowledge and behaviour, as well as the potential influence of diabetes knowledge on management behaviours. The study comprised a cross-sectional survey of 1050 adults, collecting data on age, sex, marital status, education, employment, hypertension, dyslipidaemia (any lipid imbalance, such as high cholesterol, high LDL-cholesterol or low HDL-cholesterol), smoking and diabetes status. Two multiple linear regression models were used to identify factors associated with diabetes knowledge and behaviour, and a simple linear regression model was used to assess the relationship between knowledge and behaviour. Significant associations were found between diabetes knowledge and the following factors: age (44.32 ± 9.53 for ≥50 years vs 39.73 ± 9.95 for 18 to <25 years; p<0.0001), sex (49.00 ± 12.35 for women vs 45.09 ± 13.27 for men; p<0.0001), marital status (50.92 ± 11.69 for married vs 45.39 ± 13.10 for single; p<0.0001), smoking status (45.78 ± 13.22 for smokers vs 48.22 ± 12.15 for non-smokers; p=0.003), hypertension (46.46 ± 13.11 for present vs 47.31 ± 12.87 for absent; p=0.007) and diabetes status (69.49 ± 17.35 for present vs 62.76 ± 16.88 for absent; p<0.001). Behaviour scores correlated similarly with these factors except for diabetes and smoking status. The adjusted simple linear regression model revealed that diabetes knowledge was significantly associated with better management behaviours (coefficient=0.0794, p<0.001) after adjusting for demographic and clinical factors. This study highlights the importance of demographic and clinical factors in the context of diabetes knowledge and behaviours, underscoring the need for targeted educational and preventive programmes to improve diabetes management, especially in vulnerable populations. Additionally, the strong association between diabetes knowledge and management behaviours supports a knowledge-attitude-behaviour (KAB) model of diabetes management.