In the neo-epoxy resin concrete assembled truss, truss joint serves as a very important core part. The truss joint studied herein is made of neo-epoxy resin concrete, which is connected by a chord member, a web member and a joint plate through the bolt in assembled connection. This paper introduces the theoretical basis of material constitutive relations, analysis hypotheses and boundary conditions, establishes finite element models on K-type joint of neo-epoxy resin concrete assembled truss under three different joint plate thicknesses, performs simulation analysis, studies the impact of joint plate thickness on the stress state of the K-type joint web member, chord member, joint plate and steel bar of the neo-epoxy resin concrete assembled truss. The optimal design recommendations for joint plate thickness are given to lay the foundation for optimizing joint design of neo-epoxy resin concrete assembled truss.