The North China plate is obviously different from the South China plate in Gravity anomaly and geological-tectonic characteristics. Statistic analysis of the correlation between Bouguer gravity anomaly and crustal thickness has been made for these two plates respectively, and it is found that they are remarkably different in correlation coefficient, regression coefficient and the calculated density difference between the crust and the mantle. These diffe rences suggest that North China and South China have different ciustal and upper mantle textures, which must have had to do with the different tectonic evolutions of these two great plates.