Based on the data from a national survey, this paper uses negative bionomial model and Logit model to analyze the influence of generational differences and occupational stratification to migrant workers' occupational mobility. The results show that there exist significant association between the migrant workers' occupational mobility and their occupational stratification. Those with jobs belonging to middle level have the strongest willing for upward mobility. Compared with the first generation, the new generation migrant workers especially t...