Emotional intelligence enables critical care nurses to be aware of self and others including patients' emotions result in patients' satisfaction and improved quality of care. The current study aims to determine effectiveness of nurses' emotional intelligence training on quality of nursing care for critically ill patients. Design: quasi experimental research design was used. Setting: General ICU, emergency unit, and coronary care unit at Sohag University Hospital. Sample: First group is: convenient sample of 70 nurses. Second group is: 420 patients were selected into two groups' pre and post nurses training. Tools: Quick Emotional Intelligence Self-Assessment Questionnaire and Patients' Perception of Quality Nursing Care Scale. Results: a highly significant relation between nurses' emotional intelligence level pre training with post training T test 3.699 at P < 0.01; a highly significant relation in patients' perception of quality nursing care T test 7.623 at P<0.01; and highly significant relation between nurses' emotional intelligence level and patients' perception of quality nursing care r = 0.767 at P<0.01. Conclusions: improvement in nurses' emotional intelligence level resulted in the improvement in the quality of nursing care. Recommendations emotional intelligence training should be introduced for critical care nurses as a basic of in-service training programs.