The use of the best teaching method to promote self-care in patients with inflammatory bowel disease (IBD) has not been well defined. Therefore, the current study was conducted to compare the effect of self-care education by two methods of teach-back and a smartphone application. The current clinical trial with a pre- and post-test design was conducted among 78 patients with IBD. Patients were allocated to three groups of application, teach-back and control using a simple blocked randomization. Data were collected using a checklist for demographic information and Inflammatory Bowel Disease Self-efficacy Scale. Collected data were analyzed using SPSS. Participants in all three groups were homogeneous in terms of demographic variables. The mean pretest scores of self-efficacy (SE) in the application, teach-back and control groups were 191.37 ± 49.15, 193.92 ± 45.54 and 192.76 ± 43.12, respectively. The mean post-test scores of SE in the application, teach-back and control groups were 224.51 ± 49.89, 207.48 ± 48.109 and 189.92 ± 40.28, respectively (P = 0.033). The results of the current study showed that self-care education by the application can better improve the mean scores of SE and its four dimensions of managing stress and emotions, managing symptoms and disease, managing medical care and maintaining remission, compared to other methods. It seems that the use of the application as a continuous and cost-effective educational strategy will become widespread in the future for patient education among most healthcare and treatment systems.