The goal of the current study was to determine how aqua aerobics activities improved school students cardio respiratory endurance and vo2max. Twenty (20) male school students, aged 15 to 17, were chosen at random from Christhuraja Higher Secondary School, Palayamkottai, Tirunelveli, Tamil Nadu, India. The chosen participants were randomly assigned to one of two equal categories: the Control Group (CG; N=10) and the Aqua aerobics activities Group (AAAG; N=10). An eight-week aqua aerobics activities regimen has been designed to test the impact of the offered training regimen on school student’s cardio respiratory endurance and vo2max. Before and after the six-week aqua aerobics activities programme, the cardio respiratory endurance and vo2max were assessed using the "Cooper 9mins run & walk test and Queen’s college step test." We examined and compared the pre-test and post-test scores using the paired sample -'t' test, and to determine the difference between both groups, we employed "ANCOVA" as a statistical analysis. According to the results of this research, school student’s cardiorespiratory endurance and Vo2max increased considerably following six weeks of aqua aerobics workouts. However, the control group showed no significant improvement since they did not participate in any particular activities.