The complex network information generated during the production process of cigarette factories limits the accuracy of traditional intrusion detection methods.In response to this,the article proposes a blockchain based method for intrusion detection in the production big data network of cigarette factories.By using blockchain technology to obtain and simplify the processing of network node information,energy values,signal-to-noise ratios,and abnormal score values are calculated to screen out abnormal nodes in the production network;Detecting network intrusion nodes by calculating the trust value of abnormal nodes.The experimental results indicate that this method has high detection accuracy.