Abstract Using survey data onmigrant workers in urban China, this paper carries out a positive study on theimpact of inner-industrial and inter-industrial job shifts on earnings growthof migrant workers. Results show that low human capital, low employment gradesand low income are the most important reasons for migrant workers to switchjobs. The migrant workers who are young, unmarried new entrants with low levelof education, no training and low income tend to change their jobs within theindustry. And those who have high income and who find their jobs by themselvesare more likely to switch jobs inter-industrially. Inner-industrial jobswitches have a significant positive impact on earnings growth of low-incomemigrant workers and a significant negative one on that of high-income migrantworkers. Moreover, inter-industrial shifts have a significant negative impacton earnings growth of migrant workers of all income levels. The inner cause forthe positive effect of inner-industrial shifts lie in the fact that thecumulative effect of years of service within enterprises is not obvious whilecontinuing engagement in the same type of job within an industry will lead toaccumulation of qualifications, which has a significant augmentation effect onearnings of migrant workers.