ABSTRACT Using the data of listed agriculture-affiliated companies with customer-supplier association information, we examine the diffusion effect of the digitalisation of listed agricultural companies on the digital transformation of agriculture-affiliated enterprises from the perspective of supply chain. We show that the supply chain diffusion effect of digitalisation mainly exists in ‘customer enterprises-suppliers enterprises’ and ‘leading enterprises-other enterprises’. And the digital transformation of agriculture-affiliated customer enterprises forces suppliers to respond to customer innovation demands, thereby improving the digitalisation level of suppliers, while leading agriculture-affiliated enterprises improve the digitisation level of other agriculture-affiliated enterprises in the supply chain network through knowledge flow. Additionally, the supply chain diffusion effect of digital transformation is stronger under the conditions of smaller ‘digital divide’, lower geographic distance, the downstream consumer end and more government support of agriculture-affiliated enterprises. We provide theoretical and practical implications for promoting the digitalisation of the entire agricultural chain and improving the scale effect of digitalisation.