The influence of ecological factors on the behavioral pattern in animals is attracting research interest, particularly for drill monkeys. The aim of this study was to check if ecological changes influence behavior of captive drill monkeys. The study was carried out in Limbe Wildlife Center (LWC) from May 15th 2016 to August 15th 2016 while scan and focal samples were collected in mixed strategy. Continuous sampling started from 6:00 in the morning and ended at 6:30 in the evening, where the following behavioral categories were recorded: feeding, foraging, movement, resting, socialization, grooming, play, aggression and vocalization. Simultaneously, data were recorded on weather changes. Data analysis in this survey comprised of the descriptive and inferential statistics. The study showed a significant difference for the daily activity at different time ranges (X2=172.282 df =24 P<0.05). There was no significance between 6:8.59 am to 12:2.59 pm for foraging (X2=0.103 df =1 P=0.749). In addition, there was significance on foraging from 12 am to 2.59 pm and 3 to 6:30 pm (X2=9.607 df =1 P<0.002). The drills spent more time resting between 6 to 8.59 am and 12 to 2.59 pm (X2=6.164 df =1 P<0.013). There is a significance for feeding between 6 to 8.59 am and 3 to 6.30 pm for (X2=85.63 df =1 P<0.05). The results show that the drills spent more time feeding in the morning period than in the evening period of the day, but correlated with foraging behavior. There is a positive correlation between resting and weather changes (rain and sun) R2=0.11 P<0.05. All the age sex class categories spent less time foraging. (X2=12 df =1 P<0.05) is for time resting during the wet and (X2= 94.6 df=1 P<0.05) for sunny weather. This study revealed that ecological factors like weather and photo-period influence the behavior of drill monkeys in captivity. Key words: Weather changes, wildlife, vocalization, habitat, behavior.