Objective To investigate the relevant risk factors for early recurrence after microwave ablation for primary hepatocellular carcinoma( HCC),and to provide a reference for predicting and preventing tumor recurrence. Methods A retrospective analysis was conducted on the clinical data of 80 patients who had undergone microwave ablation for primary HCC at the Beijing You'an Hospital,Capital Medical University,Beijing,China( 2010- 2012). Factors possibly influencing early recurrence were selected for univariate analysis using logistic model. Risk factors for early recurrence of HCC after ablation were screened out for identifying the high- risk population and further guiding treatments against recurrence. Results There were 30 cases of recurrence in 6 months after ablation,accounting for a recurrence rate of37. 5%. Univariate analysis showed that no significant differences occurred between the recurrence and non- recurrence groups in age,gender,tumor location and size,family history of HCC,drinking history,HCC resection history,preoperative alpha- fetoprotein level,liver function Child- Pugh grade,MELD score,or HCC- related causes( P > 0. 05). In contrast,the number of tumors( ≥2) significantly differed between the two groups( P = 0. 008). Conclusion The number of tumors is an independent risk factor for early recurrence among patients after microwave ablation for HCC. High- risk population can be predicted according to the risk factors for early recurrence after microwave ablation for HCC. Targeted preventive measures should be taken for early detection and timely treatment of tumor recurrence.