There are two composite plutons, Fucheng and Zhulanbu, emplaced in the Huichang region of the northern Nanling Mountains. Nevertheless, very insufficient researches have been conducted on the Zhulanbu composite pluton, and its age and petrogenesis remain problems of much controversy. The Zhulanbu composite pluton consists of early intrusive coarse-grained biotite mozonite and late intrusive fine-grained mozonite, and LA-ICP-MS zircon dating suggests that they were formed in Indosinian (228 Ma) and Late Yanshanian (135~133 Ma), respectively; however, the Fucheng composite pluton was emplaced in Indosinian. Chemical analyses of major and trace elements indicate that both the early and late granitic intrusive bodies of the Zhulanbu composite pluton are characterized by intermediate-strong peraluminous nature, high content of Si, Al, K, low content of Ca, Mg, enrichment of Rb, Th, U, and depletion of Sr, Ba, P, Ti, Eu. They also have lower ΣREE (<165×10^-6 on average) and Zr + Nb + Ce + Y content (<350×10^-6). These geochemical characteristics suggest S-type granites. The whole rock Sr-Nd isotopic analysis results show that the early intrusive granite exhibits higher (⁸⁷Sr/⁸⁶Sr)_i than the late counterparts (0.715 6~0.726 0 and 0.710 5~0.716 4, respectively), but they exhibit the same variation of εNd(t) values (ranging from -10.0 to -7.0). Zircon in-situ Lu-Hf isotopic analysis indicates their similarities of εHf(t) values (-12.9~-7.7 and -15.1~-10.5, respectively) and t_DM^C (2.0~1.7 Ga and 2.1~1.8 Ga, respectively). The elemental and isotopic results suggest that the Zhulanbu composite pluton probably originated from the partial melting of a mixed crustal source involving the Paleoproterozoic metapelite and minor metagreywacke. The Fucheng composite pluton and the early intrusive granite of Zhulanbu composite pluton were formed in a compressive background of the Tethys tectonic domain during the Indosinian; in contrast, the late intrusive granite of Zhulanbu composite pluton was formed in the intraplate extensional environment of the paleo-Pacific tectonic domain during the Yanshanian period.