The objective of this paper is to analyze the internal immigrants who have left their household registration areas (countryside, town, and street) for over six months. Based on the Fifth National Population Census, we found that there were 144 39 million cross countryside town street immigrants, 78 76 million cross county city immigrants, and 42 42 million cross province immigrants in the Mainland China, which accounted for 11 6%, 6 3%, and 3 4% of the total population in China respectively The highest proportions for the cross province immigrants appeared in the areas of Shanghai, Beijing, Guangdong, Zhejiang, Xinjiang, and Tianjin. The highest proportions for the cross-province emigrants appeared in the areas of Jiangxi, Sichun, Anhui, Hunan, Guangxi, Hubei, and Guizhou.