Abstract: Based on acoustic response signal analysis method，an on-line detection system for eggshell crack was designed.The system included motion control module and acoustic signal acquisition and analysis module.The system could complete the automatic knocking and audio signal acquisition for the eggs on-line delivery.Test results showed that detection accuracy of intact eggs and cracked eggs was 92% and 100% respectively.The detection system has high detection rate and stability for eggshell crack recognition，which could meet requirements of practical application.