A new fluorescent derivative of D-glucose, 2-[N-(7-nitrobenz-2-oxa-1,3-diazol-4-yl)amino]-2-deoxy-D-glucose (2-NBDG), which had been previously developed for the analysis of glucose uptake activity by living cells, was investigated to evaluate its applicability for assaying the viability of yeast Candida albicans. Lineweaver-Burk plots showed the uptake of 2-NBDG to be competitively inhibited by D-glucose and not by L-glucose, which suggested the involvement of the glucose transporting system of C. albicans in the uptake of 2-NBDG. A good correlation was obtained between the yeast viability, determined by the plate-count method, and the 2-NBDG uptake activity of yeast cells (correlation constant : r = 0.97). This is expected to lead to the development of a new fluorescent probe for the determination of yeast cell viability.