The seismicity in the territory of China, a seismotectonically complicated region, has been examined by using some complete samples of the earthquakes occurred during the last two centuries (1800 - 1999). The A-value of the Gutenberg-Richter relation was estimated by using those data samples. Taking into account the fact that the b-value is spatially more stable than the a value, the b values were calculated at the nodes of a normal grid superposing on the whole area studied and their distribution were examined. The results show that the b values increase smoothly from 0.4 to 0.93. Furthermore, keeping the b values obtained fixed, the a value distribution was also examined. In order to display more detailed information about the seismicity, smaller cell surface (10000 km2) for the calculation of the a value has chosen. The mean return period for different magnitudes was also calculated for each small cell. The seismicity in the territory of China, a seismotectonically complicated region, has been examined by using some complete samples of the earthquakes occurred during the last two centuries (1800 - 1999). The A-value of the Gutenberg-Richter relation was estimated by using those data samples. Taking into account the fact that the b-value is spatially more stable than the a value, the b values ​​were calculated at the nodes of a normal grid superposing on the whole area studied and their distribution were examined. The results show that the b values ​​increase smoothly from 0.4 to 0.93. In order to display more detailed information about the seismicity, smaller cell surface (10000 km2) for the calculation of the aa value has chosen. The mean return period for different magnitudes was also calculated for each small cell.