Biomass power generation can reduce pollutant emissions and alleviate the energy crisis. However, the development of straw power generation supply chain is affected by various risk factors. Therefore, this study analyzed the causal relationship of risk factors, clarified the internal structure and feedback mechanisms of the risk factor system, and constructed the system dynamics model of the agricultural waste power generation supply chain to explore the impact of risk factors on the supply chain in terms of cost. Subsequently, simulations were carried out using the Vensim PLE software. The results indicate that environmental risk has the greatest impact on the total cost of agricultural waste power generation supply chain, followed by market risk and information risk, with technical risk having the least impact. Risk control strategies were then proposed for the most influential risks, and the system dynamics simulation was carried out. The results show that the effect of information risk control strategies is the most effective, followed by market risk and environmental risk. Finally, the corresponding risk control strategy recommendations are proposed to reduce the cost of agricultural waste power generation. This study provides a theoretical foundation for risk control in straw power generation supply chain and contributes to the sustainable development of the agricultural waste power generation industry.