With the development of Internet and big data technology, the scale of data is growing exponentially, and these data contain a lot of valuable information. As the most intuitive way of knowledge expression, knowledge map can effectively organize and express data. As an important means of knowledge map completion, knowledge inference aims to deduce new knowledge or identify wrong knowledge based on existing knowledge in the knowledge map. Different from traditional knowledge inference methods, knowledge inference methods based on knowledge graphs are also diversified according to their simple, intuitive, flexible and rich knowledge expression forms. According to the types of reasoning methods, knowledge reasoning methods based on knowledge graph can be divided into single-step reasoning and multi-step reasoning. According to the different methods adopted for each type, each type also includes reasoning based on distributed representation; reasoning based on neural network and mixed reasoning. These methods are summarized in detail, and the future research direction and prospect of knowledge inference based on knowledge map are discussed and prospected.