In this paper, the mixed thermal lattice Boltzmann model is used to simulate the flow field and temperature field around the whole pool boiling process of bubbles with different wettability, including nucleation. The mechanism of bubble growth and escape is expounded. The effects of wettability, superheat and finite heat source length on bubble dynamics are studied.The results show that the bubble growth rate on the hydrophobic wall is higher than that on the hydrophilic wall under the same superheat.The bubble detachment diameter and detachment time increase with the increase of the contact Angle, the bubble detachment diameter on the hydrophilic surface increases with the increase of the finite heat source length, and the detachment time decreases with the increase of the length.The bubble detachment diameter on hydrophobic surface is independent of the finite heat source length, and the detachment time decreases slightly with the increase of heating length.Under different superheat conditions, the bubble escape diameter on the hydrophilic wall increases with the increase of superheat, and the escape time decreases with the increase of superheat.The superheat has little effect on the bubble detachment diameter on the hydrophobic wall, but the detachment time decreases obviously with the increase of superheat. The simulation results provide theoretical support for the further realization of complete boiling process simulation of finite heat source.