Introduction - In September 2008, an acute hepatitis B virus (HBV) infection was reported to the Gard Departmental Directorate of Health and Social Affairs involving a teenage girl who had undergone acupuncture sessions. In addition to non-compliance with standard precautions, an inspection of the acupuncture center in question noted the presence of needles and equipment that had potentially been reused. Materials and Methods - The investigation aimed to identify other cases (through mandatory reporting, public information campaigns, and letters to physicians), describe their characteristics, and compare the strains via sequencing. A case was defined as acute hepatitis B occurring in any client of the center within the previous six months. Results - A total of 4 cases (including one asymptomatic case) were identified among the center’s clientele in women aged 16 to 85 years; none had been vaccinated and none reported other risk factors. The chain of transmission could not be precisely identified. However, single-use needles were being reused, and the four genotype D strains showed 100% sequence homology in the analyzed regions and exactly the same S gene mutation (T131I). Conclusion - This is the first such case described in France, and the results of the investigation confirm patient-to-patient HBV transmission likely linked to the use of contaminated and/or shared equipment. In France, acupuncture is a medical procedure that requires strict adherence to standard precautions. (R.A.)