Studies have shown that COVID-19 patients with prediabetes frequently present with high plasma glucose levels on hospital admission. However, whether the glycemic abnormalities are temporary or persist after recovery from the illness is unclear. We conducted a prospective cohort study of 69 COVID-19 patients with prediabetes (HbA1c 5.7-6.4%) who were admitted to a tertiary care hospital in Chennai, India, from May to October 2020 and were discharged alive. Over a mean follow-up of 146.6 (SD: 72.5) days, the mean fasting plasma glucose rose by 16.8 mg/dl (from 119.3-136.1 mg/dl), 2-hr post-prandial glucose by 61.0 mg/dl (from 176.2-237.2 mg/dl), and HbA1c by 0.6% (5.9-6.5%). Of the 49 (84.5%) patients who were discharged with glucose-lowering medications, 40 (81.6%) continued taking them at the first follow-up visit (mean of 50.1 days from admission), and 39 (79.6%) continued taking them at the second follow-up visit (mean of 114.3 days from first the follow-up visit). In addition, 12.1% of patients developed new-onset diabetes after recovery from the illness. Continuous monitoring of glycemia and detecting new-onset diabetes in COVID-19 patients with prediabetes after recovery are essential, as the metabolic effects of SARS-CoV-2 persist for several months.