The purpose of the study was find out the effects of circuit training and fartlek training on selected physical fitness variables (speed, flexibility, muscular strength and muscular endurance) of the male schoolchildren’s. For the present study, sixty school boys’ students studying from Mahatma Gandhi intercollegiate, Gorakhpur (U.P) were selected randomly as subjects. Their age ranged from 13 to 17. Twenty subjects were distributed into three equally groups. Control group (N=20), Group – I circuit training (N=20), group–II plyometric training (N=20). The experimental groups with varied load and velocity (intensity) under went their respective training programme for three days in a week for eight weeks. Analysis of co-variance (ANCOVA) and scheffe’s post hoc tests were used to examine the significance between the variables for testing groups. The analysis was carried out using SPSS version in 17.0 and statistical significance was set to a priority at p ˂ 0.05. All physical fitness variables signifince improvement of circuit training, plyometric training and control group. The speed and flexibility no significant proved of between experimental groups and to be improved muscular strength and muscular endurance.