Health-related physical fitness refers to those components of physical fitness that are associated with health of a person. The ability to perform daily activities with vigour and having traits associated with lower risk of developing chronic diseases is a demonstration of health-related physical fitness. Physiological factors like cardio-respiratory endurance, muscular strength, and flexibility are the common measures of Health-related fitness which play an important role in carrying out day to day tasks and effects working efficiencies of an individual. The purpose of this study was to differentiate between the adolescents of low (Chandigarh & Dehradun) and high (Shimla & Srinagar) altitude with their levels of Health related Physical Fitness. For the study a total of 1000 school going male adolescents comprising (N=500) from low altitude and (N=500) from high altitude were purposively selected. To assess the level of Health related Physical Fitness of the subjects the components of Cardio-Respiratory Endurance (assessed through Nine minute run/walk test), Flexibility (measured through Sit and reach test), Muscular strength and endurance (assessed through flexed knee sit ups in 60 seconds test), Skin fold measurement (measured through triceps and sub scapular area by skin fold clipper) were worked out and compared by using descriptive statistics and ‘t’-test. The level of significance was set at 0.05. Findings of the study concluded that the adolescents belonging to low altitude are significantly better on flexibility and muscular strength & endurance than the adolescents of high altitude.