Joints are necessary components in the larger space deployable truss structures which have significant effect on the dynamics behavior of these deployable joint-dominated structures. Four kinds of joints’ nonlinear force-displacement relationship are analyzed based on describing function method. The dynamic responses of one-DOF jointed system under different exciting force levels are investigated to understand the influence of joint nonlinearity on dynamic responses. The influences of joint characterizing parameters on joint nonlinearities are analyzed. Dynamic responses of the modular beam-like deployable joint-dominated truss structure are tested under different sinusoidal exciting force levels. The experimental results show obvious nonlinear behaviors contributed by joints that dynamic response shifts to lower resonance frequency and higher amplitude with the increase of exciting force. The nonlinearity of the joints in the tested structure is compared with the theoretical results and identified to meet with the hysteresis nonlinearity. Joints are necessary components in the larger space deployable truss structures which have significant effect on the dynamics behavior of these deployable joint-dominated structures. Four kinds of joints’ nonlinear force-displacement relationships are analyzed based on describing function method. -DOF jointed system under different exciting force levels are investigated to understand the influence of joint nonlinearity on dynamic responses. The influences of joint characterizing parameters on joint nonlinearities are analyzed. Dynamic responses of the modular beam-like deployable joint-dominated truss structure are tested. The experimental results show obvious nonlinear behaviors contributed by joints that dynamic response shifts to lower resonance frequency and higher amplitude with the increase of exciting force. The nonlinearity of the joints in the tested structures is compared with the theoretical results a nd identified to meet with the hysteresis nonlinearity.