Highly dense and frequent dikes are temporally and spatially associated with gold deposits in the Guocheng area in the Jiaodong Peninsula, which mostly include diabase, lamprophyre, diorite, diorite-porphyrite, granite-porphyrite and syenite-porphyrite. In order to investigate their genesis, source characteristics and tectonic background of diagenesis, the petrology and geochemistry are reported in this paper. In terms of major elements, the dikes are attributed to the potassic calc-alkaline series as a whole. They possess high Mg, Fe, Al and low Ti contents. The dikes are rich in LILE and LREE, and relatively depleted in HFSE, suggesting a production of partial fusion (9.52%) of disseminated amphibole peridotite of enriched mantle. The magma might undergo fractional crystallization of olivine, clinopyroxene, hornblende and weak plagioclase during the diagenesis process, which however is not obviously contaminated by crust materials in the emplacement process. Meanwhile, the dikes are formed in intraplate environment but possess the geochemical features of continental marginal arc calc-alkaline basalt, implying their relationship to the Pacific Plate subduction and Late Jurassic-Early Cretaceous thinning event in the lithosphere of the North China Block, especially the sinistral strike-slip extension of the Tanlu fault zone.