Objective To evaluate the feasibility, efficiency, and safety of microwave ablation (MWA) for T1N0M0 multifocal (<= 3) papillary thyroid carcinoma (PTC).Methods This was a retrospective study, and patients who underwent MWA for multifocal (<= 3) PTC were reviewed between October 2016 and December 2020. After ablation, the changes in tumor size and volume, as well as the rate of technical success, tumor disappearance, disease progression, and complications were assessed.Results There were a total of 57 cases enrolled in the present study, which included 18 males and 39 females. The mean age was 44 +/- 11 years (22-66 years); the mean follow-up time was 18 +/- 11 months (6-48 months). Complete ablation was achieved in all enrolled cases. Therefore, the technical success rate was 100%. Due to expanding ablation, the MD and volume of the ablation zone, as well as the VRR, increased at the 1st and 3rd months after ablation and decreased at 12 and 18 months after ablation (p < 0.05 for all). The total complete tumor disappearance rate was 43.9% (25/57), including 54% (24/44) in the T1a subgroup vs. 7.7% (1/13) in the T1b subgroup (p = 0.003). The total disease progression rate was 7% (4/57), including 9.1% (4/44) in the T1a subgroup vs. 0% (0/13) in the T1b subgroup (p = 0.142). The overall complication rate was 5.3% (3/57), including 6.8% (4/44) in the T1a subgroup vs. 0% (0/13) in the T1b subgroup (p = 0.206).Conclusion This preliminary study indicates that MWA is a safe and effective treatment for T1N0M0 multifocal (<= 3) PTC.