The self-made microporous hydrophobic membrane of polyvinylidene fluoride was used to research the performance of vacuum membrane distillation by changing the influencing factors such as the inlet water temperature,influent flow,the vacuum degree of the cold side and feed concentration.The result shows that the permeation flux of membrane increases with the increase of vacuum tightness(0.038~0.093 MPa),feed flux(1.8~17.5 L/h)and feed temperature(40~65 ℃),and reaches the maximum flux at 39.22 kg/(m2·h).The permeation flux decreases while the reject rate increases with the increase of the concentration of feed(1~40 g/L).The membrane flux is only 9.59 kg/(m2·h) and the reject rate is 98.6% when the concentration is 40 g/L.