Abstract: Objective To identify the predominant communicable diseases in Lishui and provide scientific evidence for the prevention and control of communicable diseases. Methods Eight communicable diseases of viral hepatitis,hand foot and mouth disease,influenza,mumps,tuberculosis,bacillary dysentery,gonorrhea and AIDS were selected as priority diseases at municipal level,and grey association analysis was conducted to identify the predominant communicable diseases in Lishui. GM model was established to predicate the epidemic in 2010. Model accuracy was evaluated comprehensively by two indexes of posterior error ratio c and the smallest error probability p respectively. Results Correlation degree of viral hepatitis,tuberculosis,mumps,gonorrhea,AIDS,bacillary dysentery,influenza and hand foot and mouth disease were 0.94,0.94,0.89,0.81,0.77,0.77,0.75 and 0.62 respectively. Grey model had a better prediction accuracy,the predicated incidences of above communicable diseases were 102.32/lakh,41.58/lakh,67.78/lakh respectively. Conclusion The predominant communicable diseases will be tuberculosis,viral hepatitis and mumps. Viral hepatitis,tuberculosis epidemic were mitigated,but the epidemic of mumps intensified.