This study aimed to examine the effect of Body Mass Index (BMI) on physical fitness levels in women between the ages of 65-75.The research was conducted with the participation of 687 women who were able to maintain daily life activities independently, who had no serious health problems, and who could be considered healthy in their age category. The cases included in the study were divided into 3 groups as Normal (117 cases), Overweight (273 cases), and Obese (297 cases) according to the calculated Body Mass Index values. Accordingly, those with a body mass index of less than 18.50 kg/m2 were classified as Thin, those between 18.50 and 24.99 kg/m2 as Normal, those between 25.00 and 29.99 kg/m2 as Overweight and those higher than 30 kg/m2 as Obese. 687 cases were included in the study, and the categories were designed as Normal, Overweight and Obese since there were no cases below 18.50 kg/m2 within the body mass index values calculated among these cases.In the study, the Senior Fitness Test (SFT) protocol consisting of six stations designed by Rikli and Jones (2001) was used to determine the physical fitness levels of the elderly.In the analysis of the data obtained from the measurements, arithmetic averages, standard deviations, and differences between the averages were found using SPSS 11.0 for Windows package software. As a result of the Kolmogorov Smirnov test conducted to find the level of distribution of the data, it was determined that all groups presented a normal distribution. One-way ANOVA-Scheffe test was applied to compare the test scores of the cases according to body mass index values. The correlation of the body weight of the groups classified according to body mass index with the test scores was examined at the level of 0.05 and 0.01.As a result, among the cases that were grouped according to their body mass index values, the cases with normal BMI values were found to have the best physical fitness test scores. Performance differences between groups were found to be statistically significant according to their BMI values. Especially in obese individuals, it was determined that their movement skills decreased due to weight gain.