Medication errors may arise due to insufficient information on drug use. The purpose of this study was to determine the impact of educational support on standards of medication administration regarding nursing medication errors in Intensive Care Units (ICU). The study's participants included two groups of ICU nurses. Both groups were observed using a checklist, before and two weeks after training. Educational intervention in the form of two two-hour sessions was conducted for the intervention group, while control group received no intervention. No significant differences were found in both groups before intervention (P>0.05). However, the nurses' medication errors significantly decreased in the intervention group compared to the control group (12.7 ± 1.5 vs. 22.7 ± 3.8; p <0.01). Therefore, education of standards can result in a significant reduction in medication errors among ICU nurses. Even for ICU nurses, post-medical education is important for continuing professional education.