question: Objective Data on SARS-CoV-2transmission remains conflicting. Airborne transmission is still debated. However, the hospital risk-control requires a better understanding of the different transmission modes. This work aimed at evaluating the frequency and factors associated with environmental air and surface contamination in the rooms of patients with COVID-19 in the acute phase of the disease. Methods We included 65 consecutive patients and sampled for each patient: seven room surfaces, air at one and three meters, patient’s mask (inner face) and healthcare worker’s mask (external face). Environmental contamination was assessed by RT-qPCR (Reverse Transcription-quantitative Polymerase Chain Reaction) for SARS-CoV-2 RNA on surfaces, air and masks. Then, we performed a viral isolation test on Vero cells for samples having RT-qPCR cycle threshold (Ct) ≤37. Results SARS-CoV-2 RNA was detected by RT-qPCR in respectively 34%, 12%, 50% and 10% of surface, air, patient mask and HCW mask. We isolated an infectious virus in culture from 2 samples among the 85 positive ones with a Ct ≤37. By multivariate analysis, only the positivity of SARS-CoV-2 RT-qPCR on patient’s inner face mask was significant factor for surface contamination (OR: 5.79; 95% CI: 1.31-25.67; p = 0.025). Conclusion Surface contamination by SARS-CoV-2 seems to be more frequent comparatively to air or mask contamination. However, viable virus seems to be rarely documented. Patient’s inner face mask could be used as a carrier marker to identify patients with a higher risk of contamination.