Buckwheat was widely cultivated in Guizhou with a unique natural and social environment from the Ming Dynasty to the Republic of China. Through the analysis of historical documents and local chronicles, the paper aims to explore the issue of buckwheat planting in Guizhou during this period. Due to the unique natural conditions of Guizhou and the influence of immigration, political power and the idea of storing up grain against famine, buckwheat was widely spread in Guizhou; its distribution shows an upward trend over time, and its planting area developed in a zigzag pattern over time. For hundreds of years, the values of buckwheat consumption, famine alleviation, cultural and medicinal use have had a profound impact on Guizhou, alleviating its famine, promoting the diversified development of Guizhou economy and enriching the diversity of Guizhou food culture. The study of buckwheat planting in Guizhou from the Ming dynasty to the Republic of China can deepen the understanding of buckwheat planting history in Guizhou, develop Guizhou buckwheat resources, build green and high-yield buckwheat economic belt, develop buckwheat characteristic industrial chain, and provide support for rural revitalization.