Fermentation using lactic acid bacteria is known to produce lactic acid which contributing on baking expansion properties, but strains of lactic acid has different ability to degrade starch and result lactic acid. The purpose of this research is obtain fermentation cassava flour with good characteristic by protein content, cyanide content, peak viscosity using (RVA), whiteness level, and baking expansion properties. In this research, fermentation done by mixed starter Sacharomyces cerevisiae 2% and type of lactic acid bacteria (Lactobacillus plantarum, L. achidophilus, and the combination L. plantarum and L. achidophilus 1:1). The fermentation process is also done under facultative anaerobic condition, incubation of 30°C for 48 hours, starter concentrations (0, 2, 4, and 6% v/w), and the addition of nutrients skim milk powder (0, 5, 10, and 15% w/w). Selection of fermented cassava flour determined by pH, Total Titratable Acid (TTA), total lactic acid bacteria, and total plate count, the choosen result is using starter concentrations 2% and added of 10% skim milk. The second selection is determine starter of fermentation and was choosen combination of starter cultures is L. plantarum and L. acidophilus with the ratio of 1:1. The selected starter will also be observed by amilosa-amilopectin content, yield of flour, starch granule with Scanning Electron Microscope (SEM), coliform bacteria and proximat content.