This study proposes an IoT-based smart manufacturing method, which aims to improve the integration efficiency of the industrial chain and innovation chain in high-tech manufacturing. By introducing blockchain technology and cloud–edge collaborative computing optimization, our method shows significant advantages in data integrity, system response time, computing resource utilization, cost-effectiveness, data security, system interoperability, supply chain collaborative efficiency, product quality, customer satisfaction and data processing efficiency. The simulation results show that the proposed method is superior to the traditional method in all key indicators, especially in improving data integrity (98%), reducing system response time (250ms), improving computing resource utilization (CPU utilization 85%) and significantly reducing costs. By optimizing the data processing process and algorithm, our method can process and analyze big data more efficiently, thereby improving the overall performance and response speed of the system, and providing a solid theoretical and practical foundation for the intelligent transformation of high-tech manufacturing.