In the populous District of Santa Anita , located in the eastern side of Lima, which is considered urban- marginal social place ,was carried out a parasitologic study in children in five public schools by the laboratory of Parasitology of the Research Institute of the Faculty of Medicine of the San Martín de Porres University.A single stool specimen of 956 students and 936 scotch cellophane slide was taken. Parasitology techniques were: Direct examination, Faust, Spontaneus sedimentation and Graham.Results: 85% were positive and the comensal protozoa more frecuent E.nana 53.4%, E. coli 49.9% and the patogen G. lamblia 26.8 %.The helmint more prevalent was H. nana 15%. The more afected group of age were from seven to eight years, they had Protozoa 45.7% and Helmints 0.4%. E. vermicularis from Graham 35.5% with sintoms 27% and without sintoms 8.5% and were more prevalent in the five and s...