The 2017 National Prevalence Survey (ENP) aims to measure and describe the national and regional prevalence of healthcare-associated infections and antimicrobial treatments in healthcare facilities. The survey is conducted on a representative sample of French healthcare facilities using random sampling stratified by region and facility category. Between May 15 and June 30, 2017, 403 healthcare facilities participated, including 80,898 patients. The prevalence of infected patients in 2017 (4.98%, 95% CI [4.62–5.36]) is no longer decreasing, whereas previous surveys had shown a steady decline in prevalence since 2001. The prevalence of infected patients is increasing among those with certain risk factors for infection: having a malignant infection, having undergone surgery since admission, having an indwelling invasive device on the day of the survey, and in particular a catheter. The proportion of surgical site infections (SSI) among all infections increased in 2017 compared to 2012. The prevalence of patients treated with antibiotics decreased slightly in 2017 (15.38%, 95% CI [14.48–16.63]), whereas it remained stable between 2006 and 2012. The duration of surgical antibiotic prophylaxis, often extended beyond 24 hours (40%), raises questions in light of current recommendations. It is observed that one in five treatments is changed for the same reason for prescribing. Changing the antibiotic for the same indication more frequently leads to therapeutic escalation than to de-escalation. In terms of recommendations, these results suggest continuing prevention efforts targeted at the most common and severe infections, particularly surgical site infections (SSIs), bacteremias, and pneumonia. Finally, the decline in the prevalence of patients treated with antibiotics encourages continued efforts to promote the appropriate use of antibiotics.