Aims: The aim of this research was to isolate and characterize an antimicrobial substance from the Bacillus cereus type strain ATCC 14579. Methods and Results: A substance with antimicrobial activity was isolated from B. cereus ATCC 14579. The substance was produced during late exponential growth and well into the stationary phase with a maximum 9 h after inoculation. The inhibitory substance was purified by reverse-phase HPLC and shown to be highly active against closely related Bacillus spp. Clinically relevant species such as Staphylococcus aureus and Micrococcus luteus were also inhibited. The substance was characterized as a bacteriocin-like inhibitory substance (BLIS) with a molecular mass of ca 3.4 kDa. The BLIS was very heat stable, and sensitive only to pronase E and proteinase K. Antimicrobial activity was stable and high in the pH range of 2.0-9.0, and relatively unaffected by organic chemicals. Conclusions: An antimicrobial substance produced by the B. cereus type strain ATCC 14579 was characterized, with a wide spectrum of activity and the potential to be applied as a control agent against pathogenic bacteria. Significance and Impact of the Study: The present study is the first report of a substance with antimicrobial activity from the B. cereus type strain.