A model to quantitatively describe penetration change during filter clogging through a fiber filter is proposed. This model is developed using two different analytical methods and indicates that filter penetration is a function of the coefficient K and deposited dust mass in the filter. This is verified through a number of laboratory filter experiments. The coefficient K is obtained using regression analysis via the results of the experiments with different dust loading parameters. K is expressed as a function of aerosol particle diameter, efficiency, and filter material. A larger value of K illustrates a higher increasing rate of efficiency during clogging. A larger value of K also correlates with a smaller aerosol particle size and a higher penetration filter.