Abstract: To obtain the sensitivity of tissue characteristics in the temperature field of microwave ablation on lung tissue, the finite element method (FEM) was used to establish the calculation model of microwave ablation on lung tissue, the electromagnetic field coupled with temperature field. The sensitivity of electrical conductivity (σ), relative permittivity (ε), thermal conductivity (k), density (ρ), specific heat capacity (C_p) and blood perfusion rate (ω_b) were obtained based on Morris method. Four levels for each of the six parameters (σ, ε, k, ρ, C_p, and ω_b) were set to obtain the ablation area and central temperature of microwave ablation of lung tissue at 50 W and 300 s in 2D model. The sensitivity of ablation area and ablation shape was analyzed based on Morris method. Results show that blood perfusion rate, relative permittivity and electrical conductivity have a great influence on the ablation area and shape of microwave ablation of lung tissue.