The present study aimed to characterize the behavior of Bdellovibrio bacteriovorus in the presence of Staphylococcus aureus. B. bacteriovorus was co-cultured with S. aureus or Pseudomonas aeruginosa or Streptococcus mutans, in planktonic and sessile conditions. Co-cultures were studied by Field-Emission Scanning Electron Microscopy (FESEM), Scanning Transmission Electron Microscopy (STEM), turbidimetry, quantitative PCR (qPCR), and sequencing of gene Bd0108 of B. bacteriovorus. Results indicated that B. bacteriovorus comparably inhibited planktonic growth of P. aeruginosa and S.