Abstract: By using Boussinesq dynamic equations on two-dimensional vertical cross section, which include local heating perturbation caused by heat islaned, and highly truncated spectral method, a sort of stable mesoscale nonlinear equilibrium states and an analytical solution of critical velocity are obtained. It is found that local mesoscale circulation is produced by both local heating perturhation induced by heat island and nonlinear advection. Furthermore, some dynamic characteristics of local circulation forced by heat island are discussed.