Objective:To estimate the prevalence of prescribing errors before and after implementing electronic discharge prescription system in the wards of General Surgery in a tertiary care hospital in India. Methodology: Patients discharged from General Surgery wards with a prescription containing atleast one drug were selected. Discharge prescriptions were collected before and after implementing the electronic prescribing system. Patients' demographic details like age, gender, diagnosis and number days of hospital stay were recorded in the specially designed case record form. Discharge orders were scanned to evaluate the prescribing errors in these orders. Results: A total of 1045 handwritten and 1152 electronic discharge summaries were collected, of which 76.7% and 76.2% were of <60 years aged patients, 64.3% and 63.5% of male gender respectively in both the groups. Average number of drugs prescribed per prescription was 3.5 and 4.1 before and after intervention; error rate was 33% and 8.4% of drugs prescribed respectively, 46.3% of prescriptions were of illegible handwriting. The intervention of an electronic prescribing system has reduced 75% of prescribing errors. Handwritten prescriptions had 5.5 higher odds of having prescribing errors (OR 5.5, 95% CI 4.6-6.1). Conclusion: The electronic prescribing system has a high impact in reducing prescribing errors in discharge prescriptions. Handwritten prescriptions had 5.5-times odds of higher risk for prescribing errors. Increase in age, number of drugs prescribed and length of hospital stay were major predictors of prescribing errors.