The granitic gneiss mainly consists of monzogranitic gneiss, amphibole alkal i granitic gneiss and aegirinebearing monzogranitic gneiss in the Donghai area . Acc ording to their characteristics of occurrence, chemical composition, tra ce elements and rare earth elements ,and combined with previous th eoretical and experimental data, the granitic gneiss was formed by anatexis of m ica gneiss at the ultrahigh pressure metamorphic peak stage(M2) and the isothe rm al decompressional stage (M3) under the relative H2Orich fluid system. T his res earch may have an important significance to an indepth study of the ge n etic relationship between metamorphism and granitic magma generation and its geo logical dynamics in the SuLu (Jiangsu and Shandong Province) ultrahigh pressur e metamorphic belt.