Invasive fungal sinusitis is a disease affecting the immunocompromised individuals. Diabetes being the major contributor for immunocompromised conditions worldwide is a close associate of the above-mentioned disease. Various studies over a period have shown that poor glycaemic controls had detrimental effect over the condition of the patients, and it was also proved that high sugar levels contributed to high mortality rate. But the studies aimed at analysing the effect of glycaemic control in diabetics with invasive fungal sinusitis are less. In this prospective observational study, we aim to study this association. A sample size of 25 diabetic patients were selected who were suffering with invasive fungal sinusitis. These patients were treated for the disease and their blood sugar levels were recorded on the day of admission ,1 month, 3 months, and 6 months. This close monitoring along with proper pharmacological management of diabetes with lifestyle modification was done for all 25 patients and their clinical condition were recorded and analysed. Our study proved fruitful when we found a positive relation between the improving patient condition along with lowered blood sugar levels.