This paper investigates an reconfigurable intelligent surface (RIS) and dynamic metasurface antennas (DMAs) assisted satellite Internet of Things (IoT) network, where the satellite is equipped with the DMA array to reduce the onboard power consumption and to serve the primary users. In addition, symbiotic radio (SR) technology is employed to assist RIS in transmitting its information to the secondary user. We formulate a weighted sum rate (WSR) maximization problem subject to the constraint of the satellite's transmit power, the DMA weight matrix, and the RIS phase shifts. To solve this non-convex optimization problem, we first employ the Lagrangian dual transform and quadratic transform algorithms to transform it into a tractable formulation. Then, the penalty convex-concave procedure principle is exploited to optimize the RIS phase shifts, while the complex circle manifold algorithm is employed to optimize the DMA weight matrix. Simulation results demonstrate the superiority and effectiveness of the proposed algorithm over the benchmark schemes, proving that the proposed RIS and DMA assisted satellite IoT network offers significant performance advantages. Index Terms—Dynamic metasurface antenna, reflecting intelligent surface, satellite Internet of Things networks.