Abstract:The granitic rocks especilly of the Yanshanian age in southeastern China have been divided mainly into genetic types by prof. Xu keqin:namely the syntexis type and the transformation type. Some of different characteristics between two will be presented in this paper as follows: The granites of the syntexis type are distributed in the active marginal belts of continental plate and in the deep fault zones and depressions inside it, and are usually associated with comagmatic volcanic rocks of the Jurassic-Creta- ceous period. Much crystalline and glassy melt inclusions are present in the salic minerals. The formation temperature of such inclusions may be up to 870- 1020℃. Petrochemically, the granitic rocks of this type are richer .in calcium, and with higher Na2O/K0 ratio, and belong to normal series. In the (Al-Na-K)- Ca-(Mg+Fe2+) ternary diagram, their points of projection generally fall in the area of plagioclase-hornblende association the K-feldspar of such granitic rocks is mostly orthoclase with very small triclinicity (Δ<0.3),and the biotites usu- ally have higher Mg/ (Mg+Fe3+ +Fe2+) and Fe3+/ (Fe3+ +Fe2+) ratio which varies between 0.384-0.626 and 0.252-0.121 respectively. The initial ratio (Sre87/Sr86) of such rocks is generally between 0.7050- 0.712,it is believed that they have been derived from the lower crust, and ef- fcfected by the matter derived from upper mantle. The granites of the transformation type are distributed in the inland of continent and are formed in the Yanshannian as well as periods. There aee abundant gas-liquid inclusions in quartz of these granites, their formation temperature may be estimated between 290-400℃ This series of granitic nicks are prior in calcium with lower Na2O/K20 ratio, and oversatuated for alu- minium. In (Al-Na-K)-Ca-(Mg+Fe2+) diagram, the points of projection are situated in the area of plagioclase-biotite-cordierite association. The K-feldspars of such granitic rocks are mostly of ma."rimun microcline (Δ>0.8),while the biotites are generally lower in Mg/(Mg+Fe3+ +Fe2+) and Fe3+/(Fe3+ +Fe2+) ratio, varying between 0.282-0.367 and 0.0-0.097 respec- tively. These granitic rocks have especially higher initial ratio(Sr87/Sr86) (0.712- 0.738).Based upon the above-mentioned criteria, it is concluded that granites of this type would be formed in the upper and middle parts of the crust by transfor mation processes, such as metasomatism, rhcomorphism, and partial melting of chiefly geosynclinal accumulations or other crustal materials.