Internal migration in China occurs as a result of both market forces and government interventions. This paper investigates how indicators of migration have changed over the past quarter of a century using data from successive censuses, with particular attention given to the roles of regional economic development and national policy and the effects of age and education on spatial patterns of migration. The results show a surge in migration throughout the period, an increasing concentration of migration destinations and an improvement of migration efficiency prior to 2000, but a decreased focusing of migration during the first decade of the twenty-first century. Widening regional disparity has been responsible for a sharp increase of migration from the interior to the coast, and different national economic growth poles emerged as major migration destinations at different stages of economic reforms. The analyses of age- and education-specific migration flows indicate that young adults were more mobile and more sensitive than older cohorts to interregional economic differentials, and that educated migrants were more concentrated than less-educated migrants since knowledge-based industries were more concentrated than labour-intensive industries. Our findings suggest that massive eastward migration induced by unbalanced economic development and relaxed migration restrictions still persisted in the 2000s, and that the State’s recent efforts to alleviate regional inequalities were far from achieving equilibrium in the migration system.