A typical social group of rhesus macaque (Macaca mulatta) is composed of multi-males and multi-females. Females are philopatric, forming kin-bonded subgroups (i.e., matrilines). Males often disperse into non-natal groups during puberty or elder age, while adult males in the social group are mainly immigrants. This is suggested to reduce inbreeding and/or the enhancement of male reproductive success. However, adult males are frequently observed to stay in their natal group after puberty for one or few years. Although complex factors (e.g., social relationship, inbreeding avoidance, reproductive success) could respond to the dispersal, difference in reproductive success could be the main driver. Therefore, it is reasonable to hypothesize that the reproductive success of the natal males would be lower than that of those immigrant males. From March 2010 to January 2014, non-invasive sampling (i.e., fecal DNA) was adopted to test the parentage of the macaques born during 2009 and 2013 in a free-ranging group of Taihangshan macaques (M. m. tcheliensis). This group inhabits Mt. Wangwu area within the Taihangshan Macaque National Nature Reserve, Jiyuan, China. Fecal DNA samples were collected from 76 macaques, including 19 adult females and their offspring, and 6 adult males (4 immigrants and 2 natal males). The results showed that: 1) 36 out of 51 offspring could be assigned to their genetic fathers; 2) the 4 immigrants sired 34 offspring in contrast to 2 offspring sired by a natal male (ZM), and none of the genotyped offspring was assigned to BB; and 3) the average offspring for each immigrant adult males (1.97, 95% CI: [1.02, 2.91]) were higher than that of the natal adult (0.5). The findings demonstrate that the reproductive success of immigrant male rhesus macaques is higher than that of the natal rhesus males, supporting our prediction.