Biodiversity conservation of fertile farmland is becoming an important global issue. Farmland forest in agro-forestry systems plays an important role in biodiversity conservation but the importance of borders between agricultural land and forest for arthropods has been less studied. The aim of this research was to examine the influence of edge effects on arthropods community structure of farmland forest. In this study, we surveyed arthropod diversity in 2008 and 2009 at Shengan forest farm (34°31'-34°52' N, 115°00'-115°28' E), Minquan, Shangqiu, which is a typical region of the Huang Huai Hai Plain. We selected three types of man-made forest: poplar (Populus euram ericana (Dode) Guiner CL'zhonglin-46’) forest (PF), Black locust (Robinia pseudoacacia L.) forest (BF), and mixed forest with poplar and Black locust forest (PBF). We investigated arthropod community composition, biological diversity and the influence of edge effects on arthropod community structure using the sweep net sampling method and trapping method. A total of 15100 arthropod individuals belonging to three classes, 14 orders and 64 families were collected. The higher number of total individuals was found in PF and BF,the highest number of groups was in the PBF. The results indicated that the group and individual differences of arthropod diversity at the family level did not significantly differ between years (P > 0.05). However, the number of individuals among the different types of forest (df = 2, F = 59.48, P < 0.001) and the number of groups (df =2, F =15.44, P < 0.001) did significantly differ. Compared with other forests, PF have higher species richness: S _PF (9.65) > S_PBF (8.78) > S_BF (7.47). The order of values for the biodiversity index H' was: H'_PF (1.78) > H' _PBF (1.65) > H' _BF (1.46), in which the difference between PF and BF was significant (P < 0.05). There are stronger edge effects on community composition and the number of groups and individuals, in PF and BF compared with in PBF. Rare species and farmland species are more abundant in the edge than in the forest. The numbers of individuals of common species, such as Acrididae, Tetrigidae and Gryllidae (Orthoptera), were greater in the forest edges than inside the forest. By contrast, Tettigoniidae (Orthoptera) and Geometridae (Lepidoptera) were less abundant in the forest edges than inside the forest. The arthropod diversity indices of PF and BF were higher than that of PBF, but it significantly declined 40 m into the forest. The PBF has smaller edge effects on arthropod diversity. The edge effects on arthropod community structure and diversity were present up to 40 m into PF and BF, but only up to 20 m into PBF. Farmland forest strips should not be less than 80 m wide unless two types of trees are planted in which case it should not be less than 40 m wide. This approach ensures the persistence of forest species and maintains species diversity in farmland ecosystems.