Context: Junior doctors are reported to make most of the prescribing errors in the hospital setting. Aims: The aim of the following study is to determine the knowledge intern doctors have about prescribing errors and circumstances contributing to making them. Settings and Design: A structured questionnaire was distributed to intern doctors in National Hospital Abuja Nigeria. Subjects and Methods: Respondents gave information about their experience with prescribing medicines, the extent to which they agreed with the definition of a clinically meaningful prescribing error and events that constituted such. Their experience with prescribing certain categories of medicines was also sought. Statistical Analysis Used: Data was analyzed with Statistical Package for the Social Sciences (SPSS) software version 17 (SPSS Inc Chicago, Ill, USA). Chiâsquared analysis contrasted differences in proportions; P < 0.05 was considered to be statistically significant. Results: The response rate was 90.9% and 27 (90%) had <1 year of prescribing experience. 17 (56.7%) respondents totally agreed with the definition of a clinically meaningful prescribing error. Most common reasons for prescribing mistakes were a failure to check prescriptions with a reference source (14, 25.5%) and failure to check for adverse drug interactions (14, 25.5%). Omitting some essential information such as duration of therapy (13, 20%), patient age (14, 21.5%) and dosage errors (14, 21.5%) were the most common types of prescribing errors made. Respondents considered workload (23, 76.7%), multitasking (19, 63.3%), rushing (18, 60.0%) and tiredness/stress (16, 53.3%) as important factors contributing to prescribing errors. Interns were least confident prescribing antibiotics (12, 25.5%), opioid analgesics (12, 25.5%) cytotoxics (10, 21.3%) and antipsychotics (9, 19.1%) unsupervised. Conclusions: Respondents seemed to have a low awareness of making prescribing errors. Principles of rational prescribing and events that constitute prescribing errors should be taught in the practice setting.