Introduction: People with diabetes are more likely to experience major health issues like cataracts and diabetic retinopathy, and persistently high blood sugar levels can cause serious conditions that leads to vision loss in order to avoid this, it is crucial to evaluate the knowledge and attitude of diabetes mellitus patients. Prolonged high blood glucose absorption in the lens of the eye, which leads to changes in its shape, resulting in vision changes.Cataracts are still the biggest cause of blindness worldwide, and this is especially true in India.Objectives 1. To assess the level of knowledge and attitude regarding cataract and its management among diabetic mellitus patients at IMS and SUM hospital 2. To find out association of level of knowledge and attitude regarding cataract and its management with selected socio-demographical variables among diabetic mellitus patients at IMS and SUM hospital.Methodology: It was a quantitative study conducted among 383 subjects who visited endocrinology OPD, IMS & SUM hospital, Bhubaneswar, Odisha selected descriptive, quantitative study through purposive sampling technique. It was assumed that the margin of error is 5%. The data was collected by standardized socio demographic questionnaire, knowledge and attitude questionnaire.Results: The finding shows that maximum samples between age group 51-65. This included both the male and female population of 50.7% and 49.3% respectively.. It was observed that 91.9% had a basic knowledge of cataract. 68.9% of the subjects have a positive attitude toward cataract and its management in diabetes mellitus patients. It was observed that there is no significant difference between socio demographic variables with level of knowledge. An association of attitude and socio demographic variables in the subjects put forward that there was significant difference between socio demographic variables like educational status, regular eye check-up, last eye check-up and source of information and that of attitude.Conclusion: Although majority of the patients know that DM affects the eye, that leads to cataract. The importance of better control of DM and regular eye examination in the prevention of cataract should be emphasized.