Based on assuming that there is the precursor film in the front of the apparent contact line(ACL),a model was proposed to understand the dynamic wetting process and associated dynamic contact angle.The present model indicated that a new dimensionless characteristic parameter,λ,affects the dynamic wetting process and asso-ciated dynamic contact angle as well.However,the previous model suggested that the dynamic contact angle is de-pendent on the capillary number and static contact angle only.An experimental investigation was conducted to measure the dynamic wetting behavior of silicon oil moving over glass,aluminum and stainless steel surfaces.It concluded that when the value ofλwas selected as 0.07,0.16 and 0.35 for glass,aluminum and stainless steel,re-spectively,the experimental results were in good accordance with the prediction of the model.Furthermore,the comparison of the model with Str?m’s experimental data showed thatλis independent on the species of liquids. Apparently,λshould be interpreted as the effect of the solid surface properties on the dynamic wetting process. Meanwhile,it is found in the present experiment that the Hoffman-Voinov-Tanner law,which is valid at very low capillary number(Ca 1 orθD<10°)recommend by Cazabat,still holds for higher contact angles,even up to 70°—80°.This is explained by the present model very well. Based on assuming that there is the precursor film in the front of the apparent contact line (ACL), a model was proposed to understand the dynamic wetting process and associated dynamic contact angle. The present model indicates that a new dimensionless characteristic parameter, λ, affects the dynamic wetting process and asso-ciated dynamic contact angle as well.However, the previous model suggested that the dynamic contact angle is de-pendent on the capillary number and static contact angle only. An experimental investigation was conducted to measure the dynamic wetting behavior of silicon oil moving over glass, aluminum and stainless steel surfaces. It was that the value ofλwas selected as 0.07,0.16 and 0.35 for glass, aluminum and stainless steel, re-spectively, the experimental results were in good accordance with the prediction of the model. Future, the comparison of the model with Str? m’s experimental data showed that λis independent on the species of liquids. Apparently, λ it should be interpreted as the effect of the solid surface properties on the dynamic wetting process. However, it is found in the present experiment that the Hoffman-Voinov-Tanner law, which is valid at very low capillary number (Ca 1 or θD <10 ° ) recommend by Cazabat, still holds for higher contact angles, even up to 70 ° -80 °. This is explained by the present model very well.