Abstract: In this paper, the stress state of small crossing truss structures was investigated with the standardization design program of crossing truss of Qinghai Oilfield Company as the background, so as to build up a safe, economic and reliable truss model, avoid duplicate design and improve design quality and efficiency. Comparative analysis was mainly performed on component selection, section selection, joint intersection, internal force, deformation and rigidity. The finite element model was established by using MIDAS/CIVIL large finite element software. And finally, the factors influencing the internal force of truss structures were analyzed. It is shown that the ideal truss can be obtained by analyzing the change tendency of stress, deflection and rigidity of truss structure comprehensively. As for the truss structure with dead load as the master, its own weight increases with the increasing of its width and height, which consequently results in the increase of stress and deformation of truss members. It is adverse to the structural stress, and also uneconomical. Therefore, it is suggested to choose reasonable external dimensions when the outline dimensions of truss are designed. Moreover, both the stress and economy of truss structures should be considered.