We aimed to study the knowledge of diabetes among high-risk individuals for diabetes in the Indian state of Kerala. The baseline data collected from 1007 participants of the Kerala Diabetes Prevention Program were analyzed. Diabetes knowledge was assessed using a scale adapted from a large nationwide study conducted in India. The composite score of the scale ranges from 0 to 8. The mean age of participants was 46.0 (SD: 7.5) years, and 47.2% were female. The mean diabetes knowledge score was 6.9 (SD: 2.1), with 59.5% having the maximum possible score of 8. Of 1007 participants, 968 (96.1%) had heard the term diabetes, and of them, 84.7% know what diabetes is, 87.2% think more and more people are getting diabetes nowadays, 79.6% know that diabetes can cause complications in organs, and 75.9% know that diabetes can be prevented. While the level of diabetes knowledge was high among our participants, a quarter of them (24.1%) were not aware that diabetes can be prevented. Thus, there is a need for health promotion programs to increase the knowledge of diabetes prevention among high-risk individuals in Kerala.