Abstract: Based on the similarity comparison of WSN model and social network model, this paper proposes a trust model based on social network correlation degree in wireless sensor networks (WSN). The computing method of WSN node credit with network correlation degree is built. The sensor node trust update algorithm (SNTUA) is designed based on sliding windows. Simulation experiments prove that SNTUA is better than other two algorithms and the correctness and effectiveness of SNTUA is testified.