As an important technical approach to ensuring food quality and safety, China is actively promoting the adoption of green grain storage technology. It is of great practical significance to evaluate whether the supply and demand of green grain storage technology are coordinated. Using the coupling coordination model, barycentric coordinate method and grey relational degree model, this paper reveals the spatio-temporal characteristics and evolutionary patterns of coupling coordination between supply and demand for green grain storage technology across 31 provinces in China. The research shows that the application level of green grain storage technology is increasing year by year. The main grain-producing areas exhibit the highest application levels, the main marketing areas demonstrate the fastest growth, and the application level in the production - marketing balance regions remains relatively weak. The northeastern and eastern regions outperform the central and western regions in terms of application levels. The change of the coupling coordination level between supply and demand in the application of green grain storage technology is trending toward optimization. No province has yet achieved a highly coupled stage, and nearly half of the provinces are in the running-in stage, leaving significant room for improvement. The center of gravity for the coupling coordination degree shifted towards east and south, driven primarily by factors such as infrastructure investment, scientific and technological support, and the average profit of grain enterprises.