Background Myanmar, a low-income Southeast Asia country with an estimated population of 53.9 million, is currently facing an increasing burden of noncommunicable diseases. Research that systematically measures and reports the national prevalence of diabetes and prediabetes within Myanmar represents a gap in the literature. This study, a national survey, was conducted with the objectives of 1) measuring diabetic population, 2) measuring the prediabetic population, and 3) finding out the risk factors leading to diabetes and prediabetes in Myanmar. Method Multistage sampling was applied in proportional cluster approach to recruit a nationally representative sample of 8,575 participants from 52 townships selected to represent 332 townships across the country. The Ethical Committee of the Department of Medical Research (Lower Myanmar) approved the current study. Fasting plasma glucose and the level of glucose 2 hours after 75 g glucose load were applied, to screen for diabetes and prediabetes. Interviewer-administered questionnaires were carried out to investigate demographic and lifestyle behaviors. Stadiometer, weighing scale, measuring tape, and Omron blood pressure monitor measuring devices were used for the anthropometric measurements. Survey data analysis used STATA version 13 and application of descriptive statistics with multinomial logistic regression. Result Prevalence of diabetes in Myanmar was 10.8%: 11.5% in males and 9.2% in females. Overall prevalence of prediabetes was 19.7%: 16.5% in males and 23% in females. Increasing age, urban residence, big waist circumference, and high triglyceride level were significant factors associated with diabetes and prediabetes. Many people with diabetes were found to lack knowledge and awareness of diabetes. Conclusion Diabetes prevalence in Myanmar is high, and relatively higher than that reported in many Association of Southeast Asian Nations countries. The study findings call for urgent nationwide public health action in Myanmar such as screening people at risk of diabetes and prevention of the disease. The findings can also assist the health authority in Myanmar with the preparation and allocation of resources for diabetes prevention.