To evaluate glycaemic profiles of COVID-19 patients without diabetes receiving dexamethasone and determine factors associated with hyperglycaemia.All subjects without pre-existing diabetes receiving dexamethasone 6 mg for COVID-19 in a non-critical care setting were identified. Glucose profiles were obtained from capillary blood glucose (BG). Univariate and multivariate analyses were performed to identify factors associated with dexamethasone-induced hyperglycaemia (BG ≥ 10 mmol/L).Of 254 subjects, 129 (50.8%) were male with age 51.1 ± 18.2 years and weight 89.7 ± 26.3 kg. Hyperglycaemia post-dexamethasone occurred in 121 (47.6%). Glucose excursions began within three hours (6.8 ± 1.4 mmol/L pre-dexamethasone vs 8.7 ± 2.4 mmol/L at ≤ 3 h, p 0.001) and peaked at 7-9 h (10.5 ± 2.3 mmol/L, p 0.001 vs pre-dexamethasone). BGs post-intravenous were higher than post-oral administration for the initial six hours. Hyperglycaemic subjects were older (57.8 ± 17.5 years vs 45.0 ± 16.6 years, p 0.001), had higher initial glucose (6.3 ± 1.0 vs 5.9 ± 0.9 mmol/L, p = 0.004), higher HbA1c (5.8 ± 0.3% [40 ± 3.5 mmol/mol] vs 5.5 ± 0.4% [37 ± 4.1 mmol/mol], p 0.001) higher C-reactive protein (CRP) (100 ± 68 vs 83 ± 58 mg/L, p = 0.026), and lower eGFR (79 ± 17 vs 84 ± 16 mL/min/1.73 mHalf of subjects without diabetes experienced hyperglycaemia post-dexamethasone for COVID-19, peak occurring after 7-9 h. Age, HbA1c and CRP were associated with hyperglycaemia.