Abstract: In the transition process of traditional automakers to new energy, technology uncertainty is a key issue for enterprises to optimise R&D investment and resource allocation in both old and new technologies, which is compounded by the constraints of the dual-credit policy to increase the complexity. Based on the fuzzy control and system dynamics methods, a dual-vehicle co-production R&D model is constructed to take into account the technology uncertainty under the dual-credit policy. The results show that: ①Uncertainty in the technology of new energy vehicles under the dual-credit policy mainly affects the number of credits that enterprises can sell and the speed of profit recovery, while uncertainty in the technology of fuel vehicles affects the number of credits that enterprises need to buy and the degree of profit loss. ② Enterprises that do not dominate the traditional fuel vehicle market should focus their existing resources on independent research and development of new energy vehicle technology, while for enterprises that have dominated the fuel vehicle market for a long time, they need to choose the appropriate innovation path strategy depending on the degree of uncertainty of the old and new technologies. ③ Traditional vehicle enterprises need to prioritise the control of the fuel vehicle technology that is regarded as already mature in the process of research and development, and reduce the technical uncertainty risk of the R&D of new energy vehicles on this basis.