Aim. The aim of this study was to examine the effect of teach back learning strategy on illness perception, nutritional knowledge and dietary adherence in people with hypertension. Background. Because of the chronicity of hypertension and the importance of nutrition in hypertension control, illness perception and nutritional knowledge play an important role in adherence to nutritional regimen and disease control. Method. The present study is a quasi-experimental study control group and pretest-posttest design. Based on random sampling, two health care centers in Ferdows were selected as the place for experimental and control group. Using a simple randomized method, of patients with hypertension, 35 individuals were recruited for each group. These people entered the study based on inclusion criteria and after that they signed the consent form. Before and after the intervention, illness perception, nutritional knowledge and dietary adherence were measured by self-report questionnaire and compared between the groups. Findings. After intervention, the mean score of nutritional knowledge in experimental and control group was 48. 17± 5. 21 and 41. 16± 0. 51, respectively, and a statically significant difference was found between groups in terms of nutritional knowledge (P≤ 0. 0001; t=9. 56). After intervention, the mean score of illness perception in experimental and control group was 9. 75± 1. 81 and 7. 72± 1. 60, respectively, and there was a statically significant difference between groups in terms of illness perception (P≤ 0. 0001; t=4. 15). But no statically significant difference was found between experimental and control group in terms of dietary adherence (17. 55± 4. 17 against 16. 88± 3. 62). Conclusion. Given the positive effects of teach back method and the special role of nurses in patient education, attention to this teaching method seems necessary. The use of this method of training is suggested as part of care process to reduce patients' clinical problems.