OBJECTIVES: The fertility health of the migrating population has attracted significant attention. This study examines the impact of obtaining urban citizenship on fertility among rural female migrants in China. METHOD: Utilizing data from CMDS spanning from 2011 to 2018 and pilot implementation times collected manually for 286 prefecture-level cities, we employ a staggered DID framework by comparing differences between control and treatment groups before and after policy implementation. RESULTS: The results indicate that obtaining urban citizenship significantly increases the fertility rate of rural female migrants by 1.5% points. The positive effect is primarily observed among migrants with low to medium education levels, those with medium-term migration duration, and those in low to middle-income groups, particularly for their first childbirth. CONCLUSIONS: These findings indicate that the citizenization of rural migrants significantly increases fertility rates. To alleviate the current dilemma of low fertility rates in China and other countries worldwide, governments must prioritize the elimination of differentiation and create a fertility-friendly social atmosphere.