A survey of white-throated monkey (Cercopithecus erythrogaster) in Okomu National Park, Edo State, Nigeria was conducted to estimate the population density and determine the effect of hunting activities on the population of the monkey in the study area. Two censuses were conducted using the line transect method of wildlife population assessment and the direct method of sighting. Forty structured questionnaires on hunting activities were distributed to hunters randomly selected from sixteen support zone communities in the study area. Mean population density of white-throated monkeys in Okomu National Park was 14/km as against 0.5/km recorded for the Cross River Gorilla in Afi mountain Wildlife Sanctuary, implying that hunting activities was low in the Park. Over 90% of the hunters who were predominantly youths (25 - 29years) hunted within the buffer zones and community forests. High hunting activities of the dry and festive season months (December - March) were associated with the high prices offered for bush meat during this period. The age class of the hunters is a threat to wildlife conservation in the Park as these youths are energetic and restive. It was therefore recommended that alternative employment be provided for the youths around the National Park to check further decimation of wild animals.