Effect of insulin relies on correct dose and appropriateness of insulin injection technique. However, inappropriate technique is common among diabetes patients. The impact of educating proper technique in these patients is still under studied. To evaluate the outcome of education of insulin injection technique to diabetes patients who are on insulin therapy in a Malaysian primary care clinic. A total of 114 diabetes patients on insulin were randomly selected in this prospective study. Participants' injection technique and HbA1c were assessed at baseline and 3 months later. After initial assessment, all participants were taught on proper technique of injection. Those with inappropriate technique were given individualized coaching. Majority participants (86.8%; 99/144) had appropriate technique at baseline and 67.7% (66/99) of them managed to improve their technique after intervention. There was 0.82% reduction in HbA1c observed among all participants, mean (SD) HbA1c at baseline was 9.9 (2.11)% and at post-intervention was 9.1 (2.16)%, (p < 0.01). Inappropriate insulin injection technique is very common in current study. With focused education, 67.7% (66/99) of the respondents' had improvised their injection technique. There was 0.82% reduction in HbA1c measurements within 3 months post intervention {pre 9.9 (SD 2.16) %, vs post 9.08 (SD 2.16) %}. There is a necessity to assess insulin injection technique during every follow-up. Health care providers need to identify and rectify the incorrect the technique as it may improve the glycaemic control among diabetes patients who are on insulin devices.