Aureobasidium pullulans DSM - 73015 grown on modified Biely’s medium with different carbon sources at 1% concentration secreted very low levels of β -1,4-xylanase (148.4 - 4680.9 nkat mL^-1 ; 675.1-9752.0 nkat/mg protein). Xylose was the best carbon source inducer upon addition of EDTA and NH₄NO₃ simultaneously into the culture medium. In this case , both the volumetric and specific activities increased up to 4680.9 nkat mL^-1 and 9752.0 nkat/mg protein. The highest volumetric ( 13080.9 nkat mL^-1 ) and specific activity (14964.6 nkat/mg protein) were obtained after 96 h of cultivation on 3% xylose-containing medium supplemented with EDTA and NH₄NO₃ at 0.06% and 0.6% (w/v) concentrations, respectively at an initial pH value of 4. Added EDTA showed concentration-dependent stimulatory effect on β-1,4-xylanase synthesis and about 16.7-22 and 1.5-22 folds increase in both volumetric and specific activities were achieved compared to that obtained initially on Biely’s medium at 1% xylose concentration.