Introduction: Length of femur is the good marker of late gestational age. Femur length denotes exact gestational age and helps in classification of fetus as pre-term, term or post-term. Also, it is an important parameter in medicolegal cases like decomposed fetuses, infanticide and mutilated parts of fetus. This study was mainly conducted to estimate the gestational age from human fetal diaphyseal length of femur. Material and Methods: Study was conducted on 35 human aborted fetuses obtained from OBGY department of MGM Medical college, Aurangabad and 70 femurs of right and left side were dissected out in Anatomy department of same institute for the fetal femur morphometry and its correlation with gestational age. Fetuses were divided into 4 groups as A, B, C, D according to their gestational age and diaphyseal length i.e., measurement from greater trochanter to lateral condyle (L1) was measured. Results: In each group following parameter was analyzed by descriptive statistics. The Mean +SD, minimum and maximum values for diaphyseal length of femur (L1) was calculated in each group. L1 of right femur increases gradually from 38.96 mm in group A to 74.294 mm in 32 in group D. Similarly for left femur, the diaphyseal length increase gradually from 38.971 mm in group A to 76.594 mm in group D. The mean diaphyseal length L1 of both right and left side is 38.95 in group A and 75.44 in group D, shows linear correlation with gestational age. It was found that femur length gives a positive correlation with gestational age. Conclusion: Diaphyseal length of fetal femur, is one of the most important parameter for the estimation of gestational age in 2nd and 3rd trimester.