Due to social transformation in China, more than 100,000,000 people are migrating within the country. Many parents are forced to leave their children behind when they migrate. In 2008, 58,000,000 children were living as left-behind children, mainly in the rural parts of China (Zhang, 2009).

Migration and its accompanying stressors may affect the mental health of the left-behind children. This unique literature review of Chinese literature summarises the present state of knowledge and reviews the influential factors. Possible approaches to intervention and system reforms are discussed.

A literature review was performed of published studies between 2001 and 2008. Databases used were Fujian Medical University Library Interface, Chinese National Knowledge Infrastructure, Wanfang Data, and VIP Information. The Chinese word for 'left-behind' was used as a key word. Books, book chapters, monographs and studies on caring were searched electronically and by hand. Altogether, 53 items were found, discussed and grouped together. Migration affected the mental health of the left-behind children in a passive way, especially their emotions and social behaviour.

There is still controversy over how serious mental health problems are among children who have been left behind. Life events, personality, coping strategies and social support can be regarded as four main factors that are predictive of mental health, which provides theoretical guidance for intervention. Support and prevention of mental health problems in schools, in families and in primary care should be developed and studied.