Objectives: Gutouya granitic body is one of Yanshanian acid intrusions in Xixia County, southwest Henan Province, locaded in northern Qinling Mountains. Petrogenesis and deep process of Gutouya granite are important to recognize Yanshanian tectonic evolution in northern Qinling Mountains.  Methods: Based on detailed observations of Gutouya granitic body in northern Qinling Mountains, we have studied the petrology, geochemistry and chronology of Gutouya intrusion. The geological implications of Gutouya granitic body was discussed. Results:The zircon U-Pb dating method of LA-ICP-MS was used to conform the age of biotite monzonitic granite sample named GTY01 from Gutouya granite. The results of 25 zircon spots in total 30 spots are concordia with 207Pb/235U206Pb/238U trendline. The 206Pb/238U ages of GTY0108 and GTY0115 are 419.3±4.6 Ma and 905.2±20.2 Ma, respectively. The weighted average 206Pb/238U age of 23 zircon spots in youngest age group from 108.4±0.9 Ma to 114.3±1.0 Ma is 111.7±0.6Ma (MSWD=1.4), which is regarded as the formation age of Gutouya granite. In chondritenormalized REE patterns of zircons in GTY01 sample, the characteristics of LREEdepleted, HREEenriched with Ce positive anomaly and Eu negative anomaly are shown. The formation temperature of zircon is from 626℃ to 769℃. In zircon/melts system of Gutouya granite, the change of partition coefficients for HREE is result of magma (fluids) mixing, which agrees with mafic microgranular enclave in Gutouya granite. Gutouya granite is characterized by higher SiO2 and alkali, and lower MgO and CaO. Compositional spots of Gutouya granite fall into highK calcalkaline series in the SiO2—K2O diagram. Samples from Gutouya granite are enriched in large ion lithophile elements and depleted in high fieldstrength elements, which has formed peaks of Rb and Tb, and troughs of Nb, Ta, P and Ti in spider diagram. In chondritenormalized REE patterns, Gutouya granite samples have shown the characteristics of LREEenrichment and HREE depletion with obvious Eu negtive anomaly, whose (Eu values are from 0.48 to 0.60, and (La/Yb)N ratios are from 5.82 to 11.19. The spots trend of Gutouya granite in LaN—(La/Yb)N diagram has suggested that the compositional change is controlled mainly by source compositon and degree of partial melting. Conclusions:Gutouya granite originated from partial melting in crust with the thickness ~40km, and its residual phases of partial melting source included hornblende and plagioclase. Gutouya granite is product of magma underplating triggered by regional lithosphere delamination. It takes ~15Ma to form Gutouya granite from source rock partial melting to solidification, and it is a lagged magmanism response to regional lithosphere delamination.