The feasibility of treating waste rolling emulsion using zirconia microfiltration (MF) membrane was investigated extensively in this paper. It was found that the pretreatment of waste emulsion can improve both the flux and the oil rejection efficiency. The flux increases with the increase of transmembrane pressure (TMP) if the TMP is less than 0.2 MPa, and the flux increased linearly with the cross-flow velocity (CFV). The flux may decline with the increase of TMP if TMP is greater than 0.2 MPa. The long-term flux declines with the increase in temperature in the range of 35-60 degrees C. The oil concentration in the feed tank will be kept within a certain range with the increase in the volume processed. In the long-term in situ tests, the mean flux can be maintained at about 80 l/m(2) h (LMH), and the oil rejection efficiency is more than 99.9%. The major operation parameters of ceramic membrane were compared with that of the polymeric membranes.