As the main heat exchanger for cooling tower, the performance of cooling tower packing will directly affect the cooling effect of the cooling tower. So it is important to develop the new cooling tower packing and test the performance. In this paper, the empirical formula of the new ramp-type packing was deduced based on an experimental study of packing performance. And the author analyse the factor affecting the number of transfer units(NTU) find that the NTU is not only related to gas-water ratio. According to the experimental study, the author deduced the new formula of the NTU and verified that the new formula of NTU is more accurate than the traditional formula Within a certain range of parameters.