Dropwise condensation on rough structures with different wettability are numerically simulated using Lattice Boltzmann method. The latent heat during condensation process together with the energy equation is taken into consideration in this paper by solving the temperature distribution equation with a source term for the phase change. Typical droplet nucleation positions and wetting states are found out at different surface wettability through numerical results. It is concluded that with the increase of strength coefficient of the fluid-solid interaction or surface hydrophobicity, the nucleation position rises from the bottom to top of the pillar, and the wetting state of droplet changes from the wetting Wenzel state to the nonwetting Cassie one. (C) 2018 Elsevier Ltd. All rights reserved.