NOVELTY - Extracting and separating L-phenylalanine from fermentation liquor by using combined technology of film separation and industrial chromatographic separation, comprises e.g. passing L-phenylalanine fermentation liquor through a ultrafiltration membrane to remove bacteria, pre-concentrating obtained clean L-phenylalanine fermentation liquor, passing it through an industrial chromatographic column to remove inorganic salt and impure acid, then removing pigment and micromolecule protein impurities by using nano filter film, concentrating it through a reverse osmosis membrane, and crystallizing.    USE - The method is useful for extracting and separating L-phenylalanine from fermentation liquor by using combined technology of film separation and industrial chromatographic separation.    ADVANTAGE - The method: has temperate temperature, easy operation, less separation steps, good selectivity and clean production; solves the problems of low product yield and large drainage quantity of the existing method; and produces L-phenylalanine with good yield and quality.    DETAILED DESCRIPTION - Extracting and separating L-phenylalanine from fermentation liquor by using combined technology of film separation and industrial chromatographic separation, comprises (i) passing L-phenylalanine fermentation liquor through a ultrafiltration membrane with trapping relative molecular mass of 100000-1000000 D to remove bacteria in the fermentation liquor to obtain clean L-phenylalanine fermentation liquor, where the operation pressure is 0.3-0.8 MPa, the operation temperature is 10-60 degrees C and the dialysis water quantity is 10-90% (in volume percentage) of the volume of the feeding fermentation liquor, then (ii) pre-concentrating the obtained clean L-phenylalanine fermentation liquor to a solid content of higher than 3-6%, passing it through an industrial chromatographic column by using water with a volume of 1-5 times of that of the fermentation clean liquor as propellant agent for separating, where the operation temperature is 20-60 degrees C, and removing inorganic salt and impure acid in the fermentation liquor to obtain chromatographically separated clean L-phenylalanine liquor, where the separated liquor of the inorganic salt is used for material of the fermentation liquor, (iii) removing pigment and micromolecule protein impurities from the chromatographically separated clean L-phenylalanine liquor by using nano filter film with trapping relative molecular mass of 100-3000 D, where the operation pressure is 1-3 MPa, the operation temperature is 10-60 degrees C and the dialysis water quantity is 10-90% (in volume percentage) of the volume of the feeding fermentation liquor, then (iv) concentrating the clean and colorless L-phenylalanine solution of the step (iii) through a reverse osmosis membrane to obtain concentrated liquor with a solid content of 3-7%, where the operation pressure is 0.5-1.5 MPa, the operation temperature is 10-60 degrees C and the dialysis water quantity is 10-90% (in volume percentage) of the volume of the feeding fermentation liquor, and then (v) again concentrating and crystallizing the concentrated liquor by using ordinary method.