The Random Amplification of Polymorphic DNA-Polymerase Chain Reaction (RAPD-PCR) analyses were applied for studying 7 Egyptian populations of crab species. The genetic distance (GD) among close collection sites was small among location 1, 2, 3, 4, 6 and 7, but those between location 5 and 8 were much larger (0.666 and 0.833, respectively). These values between the populations of Lake Timsah, Bitter Lakes, Suez, Attaka, Al-Tur, Port said, Domietta, Rashid and Abo-Qir showed that, AL-Tur population was distantly related from both Lake Timsah, Bitter Lakes, Suez, Attaka, Port-Said, Domietta, Rashid and Abo-Qir populations. Average of similarity index (SI) values among the studied populations based on RAPD analysis were 0.646, 0.229, 0.32, 0.328, 0.222 and 0.338 in respective arrangement between each pair of the populations; S.T.z with E.T.z, S.T.z with S.O.au, S.T.z with E.O.au, E.T.z with S.O.au, E.T.z with E.O.au and S.O.au with E.O.au. Lake Timsah, Bitter Lakes, Suez, Attaka, Al-Tur, Port-Said, Domietta, Rashid and Abo-Qir. It was stated that the lowest SI value (0.2) was calculated between Rashid and Lake Timsah populations and the highest similarity value (1.00) was calculated between Domietta, Port-Said and Bitter Lakes. However, lower SI values were obtained between Al-Tur and the other studied crab populations. It was emphasized that this population appeared with a unique molecular character. Where, there is low migration rate between Al-Tur population and the other studied crab populations. Moreover, the genetic relationships analysis clustered all populations together except Al-Tur population which was distant from the other populations.