  By extending our self-consistent MHD simulations for the solar wind, we study
the evolution of stellar winds of solar-type stars from early main sequence
stage to red giant phase. Young solar-type stars are active and the mass loss
rates are larger by up to ~ 100 times than that of the present-day sun. We
investigate how the stellar wind is affected when the magnetic field strength
and fluctuation amplitude at the photosphere increase. While the mass loss rate
sensitively depends on the input energy from the surface because of the global
instability related to the reflection and nonlinear dissipation of Alfven
waves, it saturates at ~ 100 times because most of the energy is used up for
the radiative losses rather than the kinetic energy of the wind. After the end
of the main sequence phase when the stellar radius expands by ~ 10 times, the
steady hot corona with temperature $10^6$ K, suddenly disappears. Chromospheric
materials, with hot bubbles embedded owing to thermal instability, directly
stream out; the red giant wind is not a steady stream but structured outflow.
