In recent years, the incidence of fungal infections has been rising all over the world. Although the amount of research in the field of pathogenic fungi has also increased, there is still a need for studies on fungal virulence. In this investigation, we focused on testing bloodstream-identified Candida albicans in experimental in vitro virulence assays. The proteinase enzyme activities of 30 C. albicans strains isolated from the bloodstream and sterile body fluids were investigated (15 colonizations, 15 infections). The spectrophotometric and plate methods were used to determine proteinase activity. The correlations between the 2 methods were compared. This study indicates that, in terms of proteinase activity, there were no statistically significant differences between strains obtained from infection and colonization sites by either method (P > 0.05).