Abstract: According to the actual demand of the clinical, the therapeutic schedule of point-by-point microwave ablation in atrial fibrillation was foused on. The relationship between input power, ablation point interval and effect after ablation in case of two adjacent ablation points were analyzed. The best fit input power and ablation point interval were found to provide some references for clinic treatment. 3D finite element models were built and thermal distribution in the myocardium was obtained based on the coupled electromagnetic-thermal analysis with 2. 45 GHz microwave power. Input powers and ablation point intervals were set to 30, 40, 50, 60 W and 0. 5, 1, 1. 5, 2 cm, respectively. Simulation results show that when the power are 30 and 40 W, the low power will lead to small ablation area; when the power is 60 W, high power will lead to the excessive heat, and the ablation area is not significantly improved than 50 W power's area. When interval between two ablation points are 0. 5 cm and 1 cm, the two points are too close to make the enough total ablation area, and the highest temperature is too high.When the interval is 2 cm, microwave ablation cannot lead a continuous and transmural ablation area.Therefore, 50 W is the best power and 1. 5 cm is the best ablation interval that can make the fit maximum temperature, a continuous and transmural ablation area and enough large total ablation area and highenergy efficiency. By using this ablation scheme, the total time ablation time in endocardial point-bypoint microwave ablation is 43. 2 s and the highest temperature is 87. 18 ℃. The length of continuous transmural ablation, maximal ablation length and maximal ablation width are 2. 486, 2. 770, and 1. 865 cm, respectively.