Parallel detection is one of the important means for quality control of water conservancy projects supervision.The most important role of parallel detection is to check the self inspection data of the construction unit,so as to supervise the normal operation of the inspection system of the construction unit.The detection frequency and procedure of parallel detection are relatively mature now,but different personnel have different understanding of the verification scope and function of parallel detection,which is also the difficulty of parallel detection implementation.Based on the scope and effectiveness of parallel inspection and verification,combined with the engineering construction practice,the paper puts forward the scope and effectiveness of concrete test block strength and raw material detection results,which better guides the construction self inspection work,and hopes to provide reference for the implementation of other projects.