Assamese Macaques (Macaca assamensis) inhabit various habitats; however, few studies have been conducted to document the selection of limestone forests by this monkey. Limestone forest is a unique habitat for primates, due to the patchy vegetation, and a large area of bare rock as well as hourly fluctuations in temperature, likely forcing monkeys to adopt unique adaptation strategy. In this study, we studied habitat use pattern of one group of Assamese macaques living in Guangxi Nonggang National Nature Reserve, Southwest Guangxi, China, to explore how these macaques use and adapt to the limestone forests. We conducted our surveys from September 2012 until August 2013. The instantaneous scan sampling method was used to collect the behavioral data, as well as to record the locations of Assamese Macaque individuals. In addition, the food availability was assessed by monitoring food trees’ phenology. We expressed the monthly utilization proportion of vertical zones as the records’ number of specific locations divided by the total records in each month. Annual and seasonal percentages were obtained by averaging relative monthly values. The differences were estimated using independent samples t-tests in normal distribution data and Mann-Whitney U-test in abnormal distribution data. In fact, for the multiple sample analysis, a Kruskal-Wallis test was used. The stepwise regression was performed to test the effects of the ecological factor on habitat use. Results showed that there were significant differences between different vertical zones in limestone forests (χ2 = 35.738, df = 3, P < 0.001). Cliff had the highest use frequency among the hill zones (41.0% ± 8.8%), followed by the hill slopes (32.7% ± 6.4%), hilltops (25.3% ± 7.1%), and flat land (1.0% ± 2.4%) (Table 2 and Fig. 2). There was no significant seasonal difference in the overall use pattern of the vertical zone by the Assamese Macaques. Different vertical zones were noticed to be used by Assamese Macaques for specific activities (Resting: χ2 = 58.075, df = 3, P < 0.001; Moving: χ2 = 36.709, df = 3, P < 0.001; Feeding: χ2 = 40.786, df = 3, P < 0.001). Specifically, the cliffs were frequently used as resting and moving sites, and the hill slopes were used as feeding sites. The utilization frequency of the cliffs in the fruit-rich season was lower than that in the fruit-lean season, which was contrary to cases recorded in the hill slopes (Table 2 and Fig. 2). As for the slope orientation, the utilization frequency of the north slope was the highest (25.3% ± 10.9%), followed by the east slope (25.1% ± 12.0%), the west slope (20.3% ± 9.9%), then the none orientation slope (18.0% ± 6.2%), and the south slope (11.3% ± 4.7%) (Table 3 and Figure 3). The utilization frequency of the south slope in the fruit-lean season was higher than that in the fruit-rich season. There were significant seasonal differences across different slope directions during the resting actively (χ2 = 13.292, df = 4, P < 0.05), showing that the utilization frequency of the south slope was higher in the fruit-lean season than that in the fruit-rich season (Table 3 and Fig. 3). Assamese Macaques’ habitat use was mainly influenced by fruits availability and environmental temperature. The fruits availability was negatively correlated with resting activity documented on the cliffs (r =﹣0.740, t =﹣3.481, df = 11, P < 0.01) and positively correlated with the resting behavior observed in the hill slope area (r = 0.808, t = 4.329, df = 11, P < 0.01). The utilization frequency of overall activities on cliffs (r =﹣0.617, t =﹣2.477, df = 11, P < 0.05) as well as the utilization frequency of the north slope in feeding (r =﹣0.764, t =﹣3.748, df = 11, P < 0.01) both was negatively and significantly correlated with the average temperature. Our results indicated that Assamese Macaques used the cliffs as a sleeping site and chose high-quality patch nearby for foraging to maximize the feeding benefits, which could be the trade-off strategy between foraging benefits and predation risks. Moreover, temperature also acted as a vital factor in shaping habitats’ use pattern in Assamese Macaques, suggesting behavioral thermoregulation was of great importance for Assamese Macaques to adapt on the limestone forests habitat.