Abstract: Grains and oils have been one of the most important branches of agricultural products in the basic necessity of daily life. The safety accidents of cereal and oil food occur frequently in recent years, leading to a gradual weakening of the consumers' trust in cereal and oil food quality and supply chain. There is a long cycle in the supply chain of cereals, oils, and foodstuffs, particularly for the complex structure and many stakeholders. It is still challenging to maintain the safety of the supply chain, especially in the field of grain purchase and sale. There are some risks to food security, such as "topping new with old", "revolving grain", and pressure on grade and price. The traceability system can serve as the product management to implement forward, reverse, and non-directional tracking of products, in order to connect all aspects of grain, oil, and food distribution. As such, an important guarantee can be provided for the quality and safety in the process of raw material collection, manufacturing, processing, storage, and transportation, as well as distribution and sales. The traditional traceability system cannot fully meet the large-scale production in recent years, such as data centralization, opaque information, easy data falsification, and easy formation of information silos. Blockchain can be taken as a next-generation disruptive technology after the Internet, with new features such as decentralization, distributed storage, anonymity, open and transparent data, and content not easily tampered with, bringing new solutions to product traceability in the grain and oil food supply chain. The article first introduced the basic meaning of blockchain technology, and then listed the development stages of blockchain 1.0-3.0, including the characteristics and application scenarios of each stage. Blockchain technology was summarized in the blockchain traceability field of grain and oil food over the past five years, with emphasis on the different architectures. The progress of blockchain-related technology was described in such fields as grain and oil food traceability, including combining blockchain and Internet of Things (IoT) technologies. The traceability system was then optimized for the blockchain storage performance for the traceability system. The basic architecture of blockchain was applied to the grain and oil food traceability, including blockchain alone and the blockchain + IoT. Some differences and difficulties were proposed to apply the blockchain in the field of grain, oil, and foodstuffs traceability, compared with the financial and industrial IoT fields. Traceability was used for the different categories of agricultural products. The current challenges were elaborated, in terms of storage performance, interoperability, traceability system portability, supervision difficulty, cross-chain, and cross-domain. The blockchain storage performance enhanced the blockchain scalability and throughput, and then integrated blockchain+IoT+artificial intelligence, as well as the cereal and oil food blockchain in the cross-domain and cross-chain. An outlook was given on the future field of cereal and oil food traceability. The finding can also provide a strong reference for the innovative application of blockchain technology in cereal and oil food.