In the search of vaccines and dmgs for the control of diseases the availability of animalrnmodels is vital. Cutaneous leishmaniasis, caused by L. aethiopica is an endemic disease inrnEthiopia. Availability of an animal model for L. aethiopica could be useful for studying therndifferent aspects of the disease. In this study, monkeys were infected with an isolate of L.rnaethiopica to develop the primate experimental model of the disease. Twelve grivetrnmonkeys (Cercopithecus aethiops) were trapped from cutaneous leishmaniasis (CL) nonendemicrnareas. Experimental infections were initiated in these animals after they werernscreened for natural infection. Inoculation of grivet monkeys with L. aethiopica parasiternresulted either in lesion or symptomless infection. One grivet monkey produced clinicalrnlesions following inoculation with promastigotes of diffuse cutaneous leishmaniasis (DCL)rnstrain of L. aethiopica. Another grivet monkey produced nodules following inoculationrnwith promastigotes of localized cutaneous leishmaniasis (LCL) strain of L. aethiopica. Inrnaddition to tlus, loss of hair at the infection site was seen in two of these animals afterrninoculation with LCL strain of Eo' aethiopica promastigotes. In order to. assess whetherrngrivet monkeys have similar immune responses as humans following infection withrnleishmaniasis, we investigated the ill vivo and ill vitro immune responses of these animalsrnto leishmanial antigens. Delayed type hypersensitivity (DTH) response as measured by skinrntesting indicated no significant response in the experimental animals. Monkeys were bledrnand the proliferative response of their peripheral blood mononuclear cells (PBMC) as wellrnas IFN-y and interleukin IL-IO production were tested ill vitro in response to leishmanialrnantigens. The finding indicated that ill vitro lymphocyte proliferative response of infectedrnanimals to live localized cutaneous leishmaniasis strain L. aethiopica promastigotes was significantly higher than controls. However, ill vitro lymphocyte proliferative response ofrninfected animals to live DeL strain of L. aethiopica promastigotes and killed parasites wasrnnot significantly higher compared to controls. Low level of IFN-y was produced afterrnstimulation with leishmanial antigen. There was no detectable level ofIL-lO productionrnafter ill vitro stimulation