Background: Junk food consumption and its consequences has become a major public health concern globally because of its deteriorating health consequences and surging prevalence. Though its adverse health consequences are widely prevalent in all age groups, children and adolescents are more at risk. It may lead to obesity and act as a risk factor for different non-communicable diseases (NCD's) like heart diseases, cardiovascular disease, cancer, hypertension, diabetes, etc. This study was carried out to explore the junk food consumption and its associated factors among adolescent students.Methods: A cross-sectional study was conducted among 538 adolescent students of Kaski district, Nepal. We used a stratified proportionate sampling technique to recruit the participants. A self-administered questionnaire was used for data collection. Descriptive and bivariate statistical analysis was performed. The odds ratio was computed to test the association.Results: The study found that more than half of the participants (60.30%) consumed junk foods over the last 30 days, more prevalent among public school participants (65.1%) followed by participants of private school (56.3%). More than half of the participants consumed salty snacks (58.7%) followed by sweets (57.5%). The time of consumption was found to be higher together with friends (83.9%). Similarly, it was consumed more while the participants were on a trip (70.1%). Consumption of junk foods was significantly associated with public school (OR: 1.44, CI = 1.01–2.06), single family (OR: 1.46, CI = 1.01–2.10), living with parents (OR: 1.64, CI = 1.03–2.63), while on travel (OR: 1.99, CI = 1.33–2.98), while reading (OR: 2.01, CI = 1.16–3.47), at home (OR: 2.20, CI = 1.53–3.16), at school (OR: 2.86, CI = 1.98–4.12), friends' influence (OR: 2.01, CI = 1.37–2.94), and junk food availability at home (OR: 1.92, CI = 1.33–2.76).Conclusion: Consumption of junk foods among adolescent students was remarkably high in both public school and private school adolescents. Regardless of adequate knowledge on harmful consequences of junk foods, school-going adolescents are consuming junk foods due to its easy availability and ready-to-use packaging. The government of Nepal should strictly standardize and regulate advertising policies and extravagant health claims advertised by junk food manufacturers. An appropriate intervention targeted to adolescents to improve food behaviors is recommended.