FIELD: chemical industry, more particularly preparation of crystalline anhydrous loracarbef solvate. SUBSTANCE: described is method of preparing crystalline monohydrate form of compound of formula I: 
which comprises drying crystalline isopropanolate form of formula I at temperatures from about 50 to about 100 C to give crystalline anhydrous form of compound of formula I and exposing crystalline anhydrous form of compound of formula I to relative humidity from about 90 to about 100 %. EFFECT: new form of loracarbef. 6 cl, 9 ex
