In this study, volumetric oxygen mass transfer coefficient (kLa) was selected as a criterion for facilitating the scale up of xylitol production by Candida guilliermondii at the bench and pilot-scale level. A kLa value of 16 h-1 was applied in reactors with volumetric capacity of 2.4 L, 18 L and 125 L. Fermentation was successfully scaled-up from the bench to pilot-scale level with all experiments demonstrating a minimum of 60% xylose to xylitol conversion efficiency. Under all evaluated conditions glycerol and ethanol were also produced as by-products of xylose metabolism. Only minor differences were observed in the fermentation profile when reactor volumes ranging from 2.4 L to 125 L were used for experimentation purposes, reaching, at pilot scale, yield and volumetric productivity of 0.55 g g-1 and 0.31 g L-1 h-1, respectively, with maximum specific growth rate of 0.26 h-1. This demonstrates and reinforces the feasibility of using kLa as scale up criterion. The use of this parameter allowed precise reproduction of results obtained at bench bioreactor level to a larger scale; this is extremely crucial and important information considering that the aim of the proposed biotechnological process is to reach the level required for the industrial viability.