To clarify the influence mechanism and action path of social networks on farmland abandonment, taking the hilly and mountainous areas of Ganzhou, China as the study area, this paper first explores the influence of farmers' social networks on abandonment; furthermore, a mediation effect model is introduced to test the inhibiting effect of farmland transfer on abandonment under the scenario of expanding farmers' social networks. The results show that the expansion of farmers' social networks directly aggravates farmland abandonment, but with the development of land transfer market, farmers' social networks help to reduce the transaction cost of farmland transfer, thus promoting land circulation and restraining abandonment. Considering the double‐edged effect of farmers' social networks on abandonment, this paper recommends that policies aimed at curbing abandonment should be channeled through local farmers‐based social networks, and encourage land transfer among farmers' relatives, friends, or neighbors, and so forth to reduce transaction cost in rural society.