This study, based on the survey data of 2740 migrant workers in Guangdong province, makes an analysis on the mechanism of migrant workers' stable employment in promoting their citizenship will, and eventually increasing their consumption. Further analysis has also been made on the impacts of urban differences on the above mechanism. The results show that employment stability has a significant positive impact on migrant workers' consumption, in addition to a mediating effect of taking the citizen's will as the intermediary variable. Results of further studies also reveal a mediating effect of citizenship will mediated across different cities. In the first-tier cities, the intermediary effect of citizen's intension is insignificant, i.e. the employment stability does not promote migrant workers' citizenship will; in contrast in the remaining cities, the mediating effect of citizenship will is significant. Therefore, it is of significance to promote the citizenship will and consumption of migrant workers by providing them more opportunities in formulating and implementing differential household register policies.