On the basis of our newly developed parameterizations of scattering properties of ice clouds in the solar and infrared bands, the ice clouds forcing over the tropics from the MODIS instruments aboard the Aqua and Terra have been investigated using the ISCCP classification. The classified cirrus, cirrostratus, and deep convective clouds based on the ISCCP ice cloud classification have been used to investigate ice cloud forcing due to different ice clouds over the tropics. The sensitivity of solar and infrared radiative fluxes at the top of atmosphere to ice cloud optical thickness, effective particle size, ice crystal shape, cloud effective emissivity, and cloud top height have been also investigated.