The variation of permeation flow as a function of time was experimentally studied from the intial fast transient to its final stabilization in the case of filtration of a yeast suspension using three industrial microfiltration membranes from Tech-Sep S.A.(01703 Miribel, France), SCT S.A. (65460 Bazet, France), and Le Carbone-Lorraine S.A.(54530 Pagny sur Moselle, France) with the same nominal mean pore diameter (0.2 mum). The influences of three operating conditions, concentration of yeast, transmembrane pressure, and velocity, were systematically obtained. The behaviors of the three membranes differ, as expected, because their structures as characterized by rugosity measurements and electron micrographs are very different. The correlation of the results is based on a two-term equation, adding a transient term to the steady flow J1 initially equal to the initial permeate flow rate J0 before any fouling minus J1. The parameters in the correlation of J1 and the transient flow term were obtained by statistical analysis of experimental results and yield a representation of the experimental results with an error on the order of 10%.