The fungi of the genus Candida are endogenous commensals of the gastrointestinal tract, vagina and skin in healthy individuals. In certain circumstances, however, they can cause a wide range of diseases, from mucosal candidiasis to severe, disseminated infections. The increased incidence of Candida infections in the last decades was linked to the increased use of medical implant devices, especially in patients with impaired host defenses. One of the main virulence factors of Candida is its ability to produce surface attached microbial communities, known as biofilms. The biofilms are defined as microbial communities encased in a matrix of extracellular polymeric substances (EPS) and displaying phenotypic features that differ from their planktonic or free-floating counterparts. The clinical consequences of Candida biofilm formation on medical devices are very important because of their increased resistance to most antifungal drugs (except echinocandins and liposomal formulations of amphotericin B). They also represent a reservoir and source for future continuing infections, and can cause the failure and need for the replacement of medical devices. The mechanisms of Candida biofilm resistance are complex, multifactorial and not completely explained. Several explaining factors have been proposed for the increased antifungal resistance of Candida biofilms, such as: altered growth, metabolic rate of biofilm cells, presence of extracellular matrix, expression of resistance genes, changes in sterol composition, presence of persister cells (a subpopulation of highly antifungal tolerant cells), and mixed species biofilm.