Objective: To make intensified analysis upon the existing difficulties in early detection for the infectious diseases outbreak in China and put forward some effective measures to improve it. Methods: Field investigation and in-depth interview were applied in 23 interviewees from different-level CDC. Results:The study findings suggest that although the timeliness of outbreak detection has been improved since SARS epidemic in China, some problems still exist, such as: ①lacking syndrome surveillance; ②report quality of infectious disease should be improved; ③difficulties of identifying the cases at lower social economic status; ④a definite financial compensation mechanism for the operation of web-based report system is absent; ⑤insufficient information exchange among different branches. Conclusion:Some effective measures must be taken including developing syndrome surveillance system; affording more education and training for related staff; increasing payout on surveillance and establishing an information exchange platform for early detection of disease outbreak.