The method of catalytic isomerization of xylene raw material consists of the fact that the xylene raw material is put into polymerisation conditions into contact with crystalline borosilicate as a catalyser with a composition expressed by the molar ratio of oxides where:M means at least one kation with valency n from group comprising tetraalkylammonium kation with 8 to 12 atoms of carbon, alkaline metal kation or mixture of these kations,Y's value is 4 to 500 andZ's value is 0 to 160,while this crystalline borosilicate is characterized by a defined x-ray pattern and assigned intensities. Isomerization conditions include temperatures of 121 to 482 degrees C, overpressure 0 to 7.03 MPa, a molar ratio of hydrogen to carbon within the range of 0 to 20 and a weight hour flow rate 1 to 20.