There is still controversy on both nature and cause for global warming. This review paper will be concerned only with effects of solar variability on climate change. The emphasis is on the progress in the study on potential mechanisms, rather than on reported correlation between solar variability and climate changes. It covers the Sun' s total irradiance observed by satellites, atmospheric △14C as a proxy indicator of solar activity, modeling of the effect of the Sun' s total irradiance on climate variation, and the influence of cosmic ray on cloud coverage.