Pediococcus acidilactici (IL01) has grown in MRS (Man, Rogosa and Sharpe) broth modified by substitution of glucose by 2.0% (MRS-2), 3.0% (MRS-3), 4.0% (MRS-4) and 5.0% (MRS-5) sugar cane blackstrap molasses. The highest acid production was obtained in MRS-5 broth maintained at a constant pH of 5.0. The highest biomass production was obtained when P. acidilactici was grown in MRS-5 broth at initial pH 6.5, while productivity was higher in MRS-2 broth (28.16%). When the MRS-2 broth was utilized at initial pH 6.5 for a 20-hour fermentation period, the highest growth rate (dx/dt) was found in a period of 8 to 16 hours (0.290 g cells/L.h), while the specific growth rate (µ) was 0.175 (h-1) for that period, differently from the 0.441 (h-1) obtained for the period comprising the 4th to the 12th hour. The growth in MRS broth was 5.08% (2.95 g/l) higher than in MRS-2 broth (2.80 g/l). The data obtained have shown that P. acidilactici has had a significant growth in molasses as the main carbon source, and that it is possible to substitute MRS glucose by this carbon source with the purpose of obtaining a more economical growth medium for the potential large scale productions.