Located in Tengjiaji of Rongcheng area, Shandong Province, the Macaokuang peridotite lies in the northeastern part of the Sulu ultrahigh pressure metamorphic belt. The protolith of the peridotite is the residual mantle harzburgite, which underwent ultrahigh pressure and then granuliteamphibolite facies metamorphism. Trace and rare earth element abundances of olivine, orthopyroxene and amphibole in the Macaokuang mantle peridotite and the orthopyroxenite veins and amphibolite veins within the peridotite were analyzed, and the result shows that Co and Ni are high and mainly concentrated in olivine, but their contents are low in orthopyroxene and amphibole, suggesting that the bulk rock is enriched in Co and Ni due to the high proportion of olivine in the rock. Although it makes up only 3%~8% of the whole rock, the amphibole controls the contents and distribution patterns of trace and rare earth elements of the bulk rock with the exception of Co and Ni. Orthopyroxene and olivine have much lower trace and rare earth element abundances than amphibole, and the element distribution patterns of orthopyroxene and olivine are quite similar to the pattern of amphibole. Amphibole in orthopyroxenite veins and amphibolite veins is more enriched in trace and rare earth elements than that in peridotite. Geochemistry of the elements shows that peridotite must have experienced repeated metasomatic actions of at least such components as Co and Nirich fluids, LREE, Ba, Sr, Tarich and Th, Uextremely low silicate fluids and carbonic fluids. Fluid metasomatism occurred after UHP metamorphism at a shallow mantle depth. Olivine, orthopyroxene and amphibole in the peridotite together with the intruded veins are characterized by normal mantle oxygen isotopic ratios and show equilibrium each other. Meanwhile, the oxygen fugacity of the peridotite is +1.0~+2.0, falling in the normal continental mantle range, implying that the rock has not experienced metasomatic action of crustal fluids. 