The objective of this study is to describe the incidence and characteristics of cryptosporidiosis in France. It was conducted by the Cryptosporidies Anofel network, a voluntary consortium of 36 hospital parasitology laboratories located throughout the country. From January 2006 to December 2007, 179 cases of cryptosporidiosis were reported (96 in 2006 and 83 in 2007). Over the two-year period, the same seasonal pattern of cases was observed, with a peak in late summer/early fall. Analysis of the data shows that 60% of cases occurred in immunocompromised patients (primarily due to HIV, 48%). Analysis by age group shows a peak in the 0–4-year-old age group. Genotyping of 137 isolates revealed a predominance of Cryptosporidium parvum (53%) and C. hominis (43%), with other animal-derived species being rare (10 C. felis, 3 C. meleagridis, 1 C. canis, 1 "rabbit" genotype of C. parvum, and 1 new genotype of C. parvum). This study is the first to provide comprehensive data on human cryptosporidiosis across all of France. (R.A.)