We present an earthquake potential estimate for magnitude 5.4 or larger earthquakes for China. The potential is expressed as the rate density, or the probability per unit area, magnitude and time, and it is based on smoothed seismicity. We constructed a special earthquake catalog, which combines previous catalogs covering different times. After deriving regression relationships, we estimated moment magnitudes for some events. Then we used the special catalog for constructing our smoothed seismicity model and testing it retrospectively. Using maximum likelihood we estimated the completeness threshold, the b-value, and the corner magnitude. We adopted a kind of Gutenberg-Richter distribution with modifications at higher magnitude and assumed a uniform b-value and upper magnitude limit derived from the special catalog. From smoothed seismicity, we estimated local a-values. We have begun a prospective test, finding that earthquakes since the beginning of 2000 are quite compatible with the model.