The purpose of study was to find out the effect of aerobic training on flexibility among endomorph students of Dr. Babasaheb Ambedkar Marathwada University, Aurangabad. Data was collected on individually through 30 Control and 30 Experimental group of subjects. The age range between 18±28 years was selected as the subject for the study. The instruction of training was given by researcher every day before starting the training in Dr. Babasaheb Ambedkar Marathwada University, Aurangabad. purposive sampling was used for collection of data. The data were analyzed using descriptive and t test. Only one variable of Physical fitness component was selected as the independent variable i.e. flexibility and sit and reach test was used for this study. The mean value and standard deviation of control group and experimental group in relation to flexibility of endomorph students was (1.75#4.03pre), (2.01#3.82post) and (2.21#3.53pre), (4.11#3.82post) respectively. Calculated t–ratio of control and experimental group was found 0.257 and 2.054 in relation to flexibility. The results of this study on the basis of statistical analysis states that the significant results were drawn. The experimental group have more efficient flexibility level than of the control group. Further the study reveals that aerobic training has all the essentials to improve flexibility level.