Introduction: Diabetes Mellitus is an endocrine disorder, characterized by hyperglycemia that is, high blood sugar levels. This is caused due to a relative or absolute insulin deficiency, a hormone produced by the pancreas. Lack of insulin, either relative or absolute affects metabolism or breaking down of carbohydrates, proteins, fat, water and electrolytes leading to an accumulation of glucose in the blood. Till the earlier part of this century, it was believed that there was no effective treatment for this condition, until the discovery of insulin, in 1922, by Fredrick Banting and his student, John McCleod1 Design: A descriptive survey approach was used for assessing the knowledge and attitude of Diabetes Mellitus patients regarding Self-Administration of insulin injection. Participants: The target population consisted of 60 Diabetic patients who were on Insulin Therapy within the age group of 40-70 years. Half of the patients were admitted and a few were attending the OPD services in Nootan General Hospital at visnagar. Interventions: Booklet information was given to the patients. Tool: Structure questionnaire was used to assess the level of Knowledge regarding Self-Administration of insulin injection and used Likert’s attitude scale to assess attitude regarding Self-Administration of insulin injection among diabetes mellitus patients. Results: In this study. The total 60 sample under the study were 38.3% sample 61-70 years, 20% sample 51-60 years, 20% sample 41-50 years 8.3% sample below 40 years of age. Distributed sample according to gender were 73.3% are male and 26.7% are female. Distribution of sample based on education is 1.7% graduated 3.3% had higher secondary, 21.7% completed secondary and 73.3% sample had completed primary education as regards 53.3% samples were unemployed 23% self-employed. According to family history 36.7% had family history of DM 63.3% had no family history. The level of knowledge regarding self-administration of the insulin injection were 81.7% had average knowledge, 13.3% had poor knowledge and only 5% had good knowledge regarding self-administration of insulin injection. The overall mean value of the diabetic patients knowledge regarding self-administration of insulin injection was 14.45 with a standard deviation of 3.326. This finding showed that the most of the diabetic patients were not much aware of self-administration of insulin injection. The level of attitude regarding self-administration of insulin injection was assessed were, only 18.3% had most favorable and 81.7% had a favorable attitude towards self- administration of insulin injection. It revealed the mean percentage of the positive attitude, which was 69.05 with a standard deviation of 5.585. These results showed that most of the diabetic patients were not having a most favourable attitude towards self-administration of insulin injection. Conclusion: The finding indicates that the Booklet information was a suitable and effective method of instruction for updating and enhancing the knowledge and attitude among patients.