Biofilms are increasingly implicated as playing a major role in waterborne cryptosporidiosis. This review aims to synthesize all currently available data on interactions between oocysts and biofilms. Initially described following a waterborne outbreak, the integration of oocysts in biofilm has been well demonstrated. Biofilms appear important in the dissemination/protection of oocysts in the environment. Consequently, it has been suggested that substrate-associated biofilms should be systematically considered in oocyst water quality assessment. The influence of physicochemical parameters has been studied on oocyst biofilm retention. Biofilm surface roughness, ionic concentration (especially Ca ), laminar/turbulent flow, shear stress, and electrostatic repulsion forces appear important to consider regarding oocyst release from biofilm. However, data analysis carried out during this review also revealed important gaps in biological interactions within biofilms, offering many perspectives for future work.