Objective To explore the effects of Omaha system on transitional care in discharged patients with colon carcinoma.Methods Patients with colon carcinoma who accepted surgical treatment in Tangshan Gongren Hospital of Hebei Province were selected as subjects. A total of 62 patients were chosen as control group with routine transitional nursing education from January 2012 to December 2013. Besides, a total of 63 patients were chosen as observation group with Omaha system nursing education based on intervention in control group from January 2014 to December 2015. The improvement of nursing outcomes and general self-efficacy in Omaha problem system was compared between two groups.Results The scores of problem recognition from four domains including physiology, social psychology, health-related behaviors and environments of patients in observation group were (1.21±0.20), (2.14±0.30), (1.23±0.72), (2.15±0.34) better than those in control group with significant differences (t=4.635, 2.695, 3.896, 14.632;P<0.01) 6 months after intervention. The score of the cancer self efficacy scale was (35.12±5.22) in observation group and (21.27±8.27) in control group with a significant difference (t=8.652,P<0.01).Conclusions Transitional care for discharged patients with colon carcinoma based on Omaha system can nicely help nurses understand the nursing needs of discharged patients and provide corresponding education and guidance according to problems so as to help patients, family members and community solve the problems that they encounter during rehabilitation course, and to improve the quality of life of them.