Chinese relation extraction adopts character-based or word-based neural networks. Most of the existing methods have word segmentation errors and ambiguity, which will inevitably introduce a lot of redundancy and noise and thus affect the results of relation extraction. In order to solve this problem, this study proposes a Chinese relationship extraction model based on multi-granularity combined with semantic information. In this model, we merge word-level information into character-level information, so as to avoid errors in sentence segmentation; use external semantic information to model polysemous words to reduce the ambiguity caused by semantic words; and adopt Dual attention mechanism at character level and sentence level. The experimental results show that the model proposed in this study can effectively increase the accuracy and recall rate of Chinese relation extraction and has better superiority and interpretability than other baseline models.