Based on the measurements of 227 Chinese listed companies' productivity during the period 2001—2007, and of the self-selection effect and learning-by-exporting effect in Chinese export enterprises, we find no significant differences in productivity between would-be exporting enterprises and non-exporting ones. The productivity in would-be exporting enterprises is not apparently higher than non-exporting enterprises, which indicates the absence of the self-selection effect and proves the significant influence of the export factor on enterprises' export overflow. At the same time, the differences in productivity growth are obvious, which indicates the presence of the learning-by-exporting effect. The ownership factor has no significant influence on the productivity growth of both kinds of enterprises, which shows that Chinese enterprises benefit from the learning-by-exporting effect rather than the self-selection effect. The study of Chinese companies' prior learning-by-exporting effect will provide strong theoretical support for their further internationalization.