Although international nutrition societies recommend enteral nutrition guidelines for patients in intensive care units (ICUs), large gaps exist between these recommendations and actual clinical practice. Education programs designed to improve nurses' knowledge about enteral nutrition are therefore required. In Korea, there are no educational intervention studies about evidence-based guidelines of enteral nutrition for critically ill patients. We aimed to evaluate the effects of an education program to improve critical care nurses' perceptions, knowledge, and practices towards providing enteral nutritional support for ICU patients. A quasi-experimental, one-group study with a pre- and post-test design was conducted from March to April 2015. Nurses (N = 205) were recruited from nine ICUs from four tertiary hospitals in South Korea. The education program comprised two sessions of didactic lectures. Data were collected before (pre-test) and 1 month after (post-test) the education program using questionnaires that addressed nurses' perceptions, knowledge, and practices relating to providing enteral nutritional support for ICU patients. After the program, nurses showed a significant improvement in their perceptions and knowledge of enteral nutrition for ICU patients. There was a significant improvement in inspecting nostrils daily, flushing the feeding tube before administration, providing medication that needs to be crushed correctly, changing feeding sets, and adjusting feeding schedules. The findings indicate that an enteral nutrition education program could be an effective strategy to increase critical care nurses' support for the critically ill. This education program can be incorporated into hospital education or in-service training for critical care nurses to strengthen their perceptions and knowledge of nutritional support in the ICU. This may improve the clinical outcomes of ICU patients.