This invention relates to a method for obtaining immobilized enzyme preparations, in particular to preparation and application of noval active conjugate of enzyme with a polymer carrier. Said conjugate possesses the properties of Longidaza drug and inhibits hyperplasia of connective tissue, and anti-inflammatory action, as well as it can be used for manufacturing stable, active and safe in use long-acting drugs in the form of a suppository, ointment, injection or cosmetic cream, and for making veterinary drugs. This method consists in conjugation of hyaluronidase with a water-soluble copolymer using carbodiimide or azide method. The conjugation is carried out with the use of copolymer N-oxide 1, 4-ethylene piperazine, (N-carboxymethyl)-1, 4-ethylene piperazine or its hydrazide, and 1, 4-ethylene piperazine of general formula where n is ranging from 40 % to 90 % of total number of cells; m is ranging from 3 % to 40 % of total number of cells; n + m + 1 = 100 %