The natural infection with parasitic helminths is common in wild rodent populations. Once such interactions are better understood in the laboratory, it will be more feasible to extend the findings to infected hosts in nature. The flukes recovered from laboratory- infected Akodon cursor at 63 days post-infection were stained with hydrochloric carmine and individually mounted on glass slide as whole-mounts. Light and laser scanning confocal microscopy studies of adult male and female Schistosoma mansoni are reported. The parasites were examined morphologically and biometrically, which was obtained in a digital system for image analysis. Parameters used were: tegument thickness, digestive, excretory and reproductive systems. The overall conclusion of this experiment is that the morphological features of adult worm were similar to laboratory mice. It has been confirmed that the grass mouse is a permissive host to S. mansoni infection.