Large mammalian species of Idanre Forest Reserve, Ondo State was assessed using the line transects method. Nine (9) large mammals were observed out of which three (3) were sighted directly, and six (6) were observed using indirect indices such as footprints, feacal droppings and animals activities. A total number of 148 large mammals were observed of which three (3) primate species; red-capped mangabey (Cercocebus torquators), mona monkey (Cercopithecus mona) and white-throated monkey (Cercopithecus erythrogaster) were sighted. Four species of antelopes; bushbuck (Tragelaphus scriptus), Maxwell duiker (Cephalophus maxwelli), yellow-backed duiker (Cephalophus silvicultor) and forest buffalo (Syncerus cafffer nanus) were also observed. Others include bush pig (Potamochoerus porcus) and the African civet (Civettictis civetta).It was also revealed that C. torquatus has a different encounter rate 0.16sighting/km but the C. mona and C. erythrogaster have the same encounter rate of 0.4sighting/km respectively. The result also showed that the reserve support more population of Maxwell duikers with 28.57% frequency of occurrence and little population of yellow-backed duiker with 0.84% frequency of occurrence. There is a very strong correlation between the sightings in the morning and evening (r=0.86, P<0.05). There are still some significant quantities of large mammals in the reserve most especially the primates (the monkeys) which if allowed settle down within the remaining forested habitat and patches within the reserve can increase in terms of population size. Therefore, sustainable management of the reserve will lead to increase in species composition of large mammalian species within the reserve. It is therefore very important to intensify awareness campaign and protection effort of Idanre Forest Reserve.
Key Words: Large mammals, Fauna, Line transect, Idanre and Forest reserve