With the development of the Internet, more and more people like to share their daily food, which makes the Internet rich in food image data. Many researchers collect food images on the Internet, label them, and combine machine learning and other methods to achieve food recognition systems. These food recognition systems can quickly help users record their daily diets and analyze their eating habits. The advanced food identification system can currently accurately identify hundreds of foods. At the same time, it can explore the food nutrition content and give food reference suggestions by accessing the food nutrition database. In this paper, we collect and evaluate large-scale food image datasets and food recognition systems.