With a rapidly-growing amount of biomedical information available only in textual form, there is considerable interest in applying NLP techniques to extract such information from the biomedical literature. Much of the research has paid special attention to extracting information about biomedical named entities. In this paper, we conducted a survey on biomedical named entity recognition and normalization, focusing on gene mention recognition and normalization. We believe this can help researchers to find work of their interest and interpret their own research.