Abstract: Controlling wind-sand disaster plays an importance role inincreasing agricultural productivity effectively in Yellow River floodplain area. The spatial distribution characteristics of wind field and protective effectiveness of three same size farmland shelterbelt networks, named network 1, 2 and 3, with different main forest belt ages (i.e.4a, 6a and 8a), were analyzed by multi-point observations in lowland of the Yellow River in Juancheng County, Heze City, Shandong Province. The results indicated that the main forest belt height and age had strong influences on the wind speed within the forest networks and their wind-break function and wind-break area increased with the main forest belt height increasing. The wind speed analysis of semivariance results in 3 forest networks showed that their variation models of wind speed were Gaussian model, Spherical model, and Spherical model, respectively, and there were strong spatial autocorrelations, in addition, the magnitude of autocorrelation values and spatial continuities were strongly related with the main forest belt ages, which performed as forest network 1<network 2<network 3. With the standard of reducing wind speed 30%-50%, the average effective protective area ratios of the 3 forest belt networks were defined as 31.0%, 40.7%, and 46.7%, respectively. Totally, the overall protective function of networks increased with the tree height increasing. These research results could provide the theory basis for improving the sustainable management of farmland shelterbelt network.