This study examined loneliness and its associations with social functioning in children across different historical times and contexts in China. We collected data from urban and rural groups of school-age children (N = 2,588; M age = 10 years) using self-reports and peer assessments. The results indicated that children in 2002 and 2005 urban groups had lower scores on loneliness than did children in 1992 and 1998 urban groups, suggesting that as urban China became a more modernized, self-oriented society, children tended to report lower levels of loneliness. Consistent with this trend, urban children reported lower levels of loneliness than did their rural counterparts in recent years. The analysis of associations between social functioning and loneliness revealed that across groups, sociability was negatively associated with loneliness, and aggression was positively associated with loneliness. The association between shyness and loneliness differed among the groups; it was negative in the 1992 urban group, positive in the 2002 and 2005 urban groups, and nonsignificant in the 1998 urban and 2007 rural groups. The different associations suggest that whether shy children feel lonely might depend on context.