Background: COVID-19 is the alarming problem for all over the world due to its fast spread infection mode and uncertainty in mortality rate. The diabetic population is prone for comorbidity with COVID-19 due to injurious fashion develops in respiratory system.

Aim: To compare the serum Lactate dehydrogenase levels in diabetic patients with COVID-19 & non diabetic patients with COVID-19.

Methodology: This comparative study was done at Ali medical center Hala New District Matiari Sindh. 42 diabetic & non diabetic clinically suspected cases COVID -19 with fever, cough, shortness of breath, non-pneumonic opacities on digital X.ray with raised TLC, ESR & CRP. The data analyzed for significance on SPSS 19 by applying student t test.

Results: The serum LDH levels was significantly raised (p<0.001) in group A contained COVID-19 patients with diabetes as compared to COVID-19 patients with no diabetes mellitus.

Conclusion:  COVID -19 diabetic population will be more prone to develop the respiratory complications.

Keywords: COVID-19, Serum LDH, Diabetes Mellitus, Respiratory Distress Syndrome.