China’s internal migrant population - rural migrant workers in particular - faces challenges in transferring their social security rights when they move from one province to another. The reasons of such challenges are various and include the following. First, the low pooling level of social security funds explains to a large extent the difficulties for migrant workers to transfer their social security rights and benefits. Second, the capacity of the social insurance administration agencies would need to be strengthened to enable them to transfer large amount of records and benefits between provinces. Third, existing household registration restrictions prevent migrant workers from joining the social security schemes for non-salaried urban and rural residents at the place of employment. Lastly, the fragmentation of social security information systems in the different regions further constrains the transfer of rights and benefits.