The invention discloses a polyvinylidene fluoride/liquid crystal blending microporous membrane and a preparation method thereof. The microporous membrane comprises the following components by mass percentage (wt%):10-30% of polyvinylidene fluoride, 0.4-4% of macromolecule lyotropic liquid crystal, 56-88.6% of organic solvent and 1-10% of additive. The preparation method comprises the following components of the microporous membrane by mass percentage (wt%) and the following steps: (1) 25-27% of cyanoethyl cellulose or cyanoethyl-ethyl cellulose is dissolved into 25-75% of N,N-dimethyl fomamide, N,N-dimethyl acetamide, N,N-dimethyl sulfoxide, glacial acetic acid or crylic acid, is put in constant temperature of 50 DEG C for 12 hours, and is stood for 72 hours at room temperature to form lyotropic liquid crystal; (2) microporous membrane components are weighted; (3) the organic solvent, polyvinylidene fluoride and additive are evenly mixed, and then the lyotropic liquid crystal is added to form membrane forming liquid; (4) the traditional technology and devices are used for weaving a hollow-fibre membrane or a striking flat membrane; and (5) the obtained microporous membrane is dipped in protection liquid for 3-24 hours to obtain the microporous membrane of the invention.