Food habits are important factors for wild nonhuman primates’ environment adaptation. White-headed langurs (Trachypithecus leucocephalus) are endemic to the limestone forest and face to the habitat fragmentation, which have to adjust the food habits to adapt the special environment. In this study, we compared the dietary data for white-headed langurs living in Chongzuo White-headed Langur National Nature Reserve over two separate study periods to evaluate interannual variations in diet. Our results indicated that young leaves were the preferred major food for the langur. The plant parts consumption pattern was similar between the two separate study periods. The consumption of young leaves was varied with the availability of young leaves, whereas the consumption of mature leaves was negative correlated with the young leaf’s availability. The consumption of plant species and diet diversity varied in the two separate study periods, which were higher in 2013 than 2016. In both 2013 and 2016, the diet diversity varied with the consumption of mature leaves, but negative correlated with the consumption and availability of young leaves. Dietary interannual variation probably linked to the phenology variations, or probably mean that the white-headed langurs has a flexible ecological adaptation coping with habitat fragmentation.