en تخصصي Special پژوهشي Research <strong>Background</strong>: Lifestyle modification is recognized as the first step of fatty liver treatment. This study was done to determine the relationship between the awareness of the Non-Alcoholic Fatty Liver Disease (NAFLD) and adolescents&rsquo; health-promoting lifestyle in senior high school students in the west of Tehran, Iran.&nbsp;<br> <strong>Methods</strong>: This descriptive-correlational study was performed on 338 high school students in 2020. The students were recruited by cluster sampling method. The data were collected by demographic information form, awareness of non-alcoholic fatty liver questionnaire, and Health-Promoting Lifestyle Profile II (HPLPII) and were expressed using frequency, mean, standard deviation, and analyzed by inferential statistical tests of ANOVA, Chi-square, independent t-test, and Pearson correlation coefficient using SPSS 20.<br> <strong>Results</strong>: The results showed that the highest Mean&plusmn;SD of health-promoting lifestyle was related to spiritual growth and self-actualization dimension (27.41&plusmn;5.53) and the lowest Mean&plusmn;SD was related to the dimension of physical activity (19.71&plusmn;6.63). There was a significant relationship between awareness of NAFLD and the health responsibility subscale of HPLP (P=0.004). Awareness of NAFLD had a direct relationship with the father&rsquo;s education (P=0.004). The health-promoting lifestyle was positively related to students&rsquo; grade (P<0.001), birth order (P=0.019), economic status (P<0.001), number of children (P=0.037), and living with parents (P=0.031), and negatively associated with the students&rsquo; age (P=0.014).&nbsp;<br> <strong>Conclusion</strong>: The significant relationship between knowledge about fatty liver and health responsibility indicates the need to increase students&rsquo; awareness of this disease to improve a health-promoting lifestyle. Therefore, it is suggested that educational interventions be provided at different levels of prevention to empower students.<span dir="RTL"></span><span dir="RTL"></span> Non-alcoholic fatty liver disease, Health promotion, Lifestyle, Awareness 263 274 http://jccnc.iums.ac.ir/browse.php?a_code=A-10-93-19&slc_lang=en&sid=1 Farahnaz Barmak fba0907@gmail.com 10031947532846007271 10031947532846007271 No Department of Community Health Nursing, School of Nursing and Midwifery, Iran University of Medical Sciences and Health Services, Tehran, Iran. Marhamat Farahaninia farahaninia.m@iums.ac.ir 10031947532846007272 10031947532846007272 Yes Department of Community Health Nursing, School of Nursing and Midwifery, Iran University of Medical Sciences and Health Services, Tehran, Iran. Mehri Bozorgnezhad Bozorgnejad.miums.ac.ir 10031947532846007273 10031947532846007273 No Department of Medical-Surgical Nursing, School of Nursing and Midwifery, Iran University of Medical Sciences, Tehran, Iran. Hamid Haghani haghani511@yahoo.com 10031947532846007274 10031947532846007274 No Department of Biostatistics, School of Public Health, Iran University of Medical Sciences, Tehran, Iran.