A model of effect of dynamical variation of tissue pressure on exchange between capillary and tissue has been presented in this paper. Filtration rate FR filtration factor FF and apparent viscosity μ of blood in capillary were got by using numerical calculation and compared with those in static condition. The results showed these important parameters varied dynamically with dynamical variation of tissue pressure. In general static condition blood apparent viscosity will increase along capillary tube then keeps in a higher level but in dynamic condition blood apparent viscosity will keep in a lower level not rise during some phase just if amplitude of dynamical variation of tissue pressure is in a suitable range. This is a reasonable explanation for Hemodynamics Mechanism of Chinese massage "huoxuehuayu".