The freshwater shrimp Atya scabra Leach, 1815 is traditionally captured in the Bia river, in the area of the South-Comoé, precisely in Biaka and Aboisso. The aim of this study was to investigate if sexual differences could affect external morphology in freshwater shrimp Atya scabra, to determine sexual dimorphism related to morphological differences during the maturation in this species. Thus, morphometric measurements in 360 specimens of A. Scabra were examined at each study site for sexual dimorphism from August 2014 to July 2015. In Aboisso, mean values recorded at lpp, Lantn and Lantl were 8.5 ± 7.8; 78.5 ± 84.1 and 47.5 ± 47.4 mm in males. The average values obtained were respectively 6.5 ± 4.9; 58.5 ± 46 and 25 ± 24 mm for lpp, Lantn and Lantl in females. In Biaka, Mean values in males were 7.5 ± 7.8; 71.5 ± 55.9 and 37.5 ± 31.8 mm. In females, mean values recorded were 6 ± 5.7; 60 ± 50.9 and 27.5 ± 21.9 mm. Concerning the sexual dimorphism index, the χ2 test showed that there is no significant difference (P > 0.05) between the SDI determined at the level of the width of cephalothorax and the 3rd pair of pereiopod (lpp) in the specimens of Atya scabra of Aboisso and those of Biaka. Analysis of the data shows two modal of distribution in males, females and in both sexes combined. When considering the sexes combined, the young recruits have an average size (Lt) of 83 ± 3.8 mm while the latter was 107.6 ± 12.1 mm in the oldest freshwater shrimps of the species A. scabra captured in Aboisso. But in Biaka, the young individuals had an average size (Lt) of 81.4 ± 4.3 mm. As for the oldest individuals, the value of the estimated average size is 107.0 ± 11.2 mm in the sexes combined. The present study was made in order to have data on the size frequency distribution and the sexual dimorphism index of this species.