Solid-liquid of two-phase flow with tiny chemical reagent is popular among industry production area，in which the dispersion of chemical reagent that having effective collision with colloid particle as well as enough contact time are quite important. The fluid shear condition has much influence on the above process. Such influence is also called fluid force chemistry effect. The concept of fluid force chemistry is illustrated，and a quite rigid definition is brought forward. In addition，the initial study and applying field are briefly introduced.