Nutrition transition may have influenced processed food consumption, particularly in middle-income countries like Pakistan. The role of processed foods in nutrition transition has been receiving greater analysis, given that such foods tend to be high in refined sugars, salt, sodium and fats (saturated and trans). The excessive consumption of these is associated with obesity and diet-related non-communicable diseases (NCDs). To find out the factors contributing towards processed food consumption and frequency of consumption on weekly basis among adolescents of schoolgoing age in Karachi across sectional survey has been conducted in this study, pertaining to six districts of Karachi with a sample size of 478 adolescents. This was done using a multistage simple random sampling technique. A validated ultraprocessed food consumption survey questionnaire was adopted. Basic demographics, factors promoting consumption of processed food items and weekly consumption pattern of different items were investigated in school-going adolescents. Of the total, around 92% of a dolescents consumed processed food on weekly basis due to taste (64%) and diversified range of items (41%). Out of these, males (59%) and older adolescents (52.3%) were consuming more processed food. Affordability (98%) and availability (94%) were found as the two main factors for the high consumption of processed food, whereas print and electronic media advertisements (91%), peer pressure (83%) and women employment (59%) were found as the promoting factors for excessive consumption. The consumable items included cold drinks (76%), breads and buns (68%), Banaspati ghee (67%), butter (64%), tetra pack sweetened milks (60%), dawn paratha (44%), jams and marmalades (43%), crisps and snacks (42%), fruit juices (40%), and chocolates (39%). Processed food consumption and its major impact on health are commonly seen in adolescent group. Convenience, affordable prices, peer influences, and heavy marketing of processed and fast food has increased the level of consumption. The study is a preliminary investigation survey providing some evidence on ultra-processed food consumption among school-going adolescents in Karachi. Future research should be done on effective nutrition intervention and promotion strategies to reduce excessive consumption of processed food among the said age group.