The shift from labor cooperation in small-scale agricultural production to market-oriented employment reflects the transformation in China’s traditional rural social network.The continuous outflow of rural labor resources triggered by external employment opportunities may be a key factor driving this marketization of labor in smallholder agriculture.From the perspective of changes in smallholder social networks，this study uses data from banana farmers in Guangdong，Yunnan，and Hainan-China’s major banana-producing provinces-to empirically examine the impact of labor outflow on smallholders’ employment decisions.It further explores the mechanisms of this impact through two dimensions of social networks：strength and breadth.Research findings are as follows：Firstly，labor outflow significantly promotes the marketization of employment in agricultural household management，shifting smallholder labor practices from reciprocal labor exchange to hired labor；Secondly，the outflow of labor has weakened the “strength” of small farmers’ local social networks in rural areas and expanded their “breadth” of social networks；The former significantly inhibits the marketization，whereas the latter markedly facilitates it.The outflow of rural labor has led to the disintegration and reconstruction of smallholders’ social networks，further inducing the evolution of labor market institutions in the context of China’s rural society.Clarifying the natural evolution process of smallholder production institutions can provide insights for enhancing specialization and organization in smallholder production cooperation.