Candida albicans has a high propensity to develop biofilms that are resistant to traditional antifungal agents. Thymol is credited with a series of pharmacological properties including antimicrobial and antifungal effects. As C. albicans biofilms are known to be important factors underlying its virulence and pathogenicity, the aim of this study was to investigate whether thymol can interfere with biofilm formation as well as acting on mature biofilms. Tests of C. albicans strains ATCC 3153A and ATCC MYA 2876 showed that thymol interferes with the starting phases of biofilm production as well as with mature C. albicans biofilms. The metabolic activity of sessile cells was reduced by >90% at twice the minimum inhibitory concentration of planktonic cells. As biofilm is a multifactorial phenomenon, the multiple mechanisms of thymol (terpenes) could act on different steps in the evolution of mature biofilm.