Modification of cassava flour(MOCAF) is fermented cassava flour biomass with the help of microorganisms. Modification of cassava flour has a protein content and properties of the physicochemical better than regular cassava flour (without fermenting). Manufacture of modified cassava flour through several stages, namely the preparation of cassava (peeling, washing and cutting), fermentation, drying and the process of conversion chips dried into flour. Modified cassava flour can be produced by fermentation using a wide variety of microorganisms such as the culture of the Lactobacillus casei group of lactic acid.This research aims to know the influence of the concentration of a starter, a thick piece of cassava chips and the addition of nutrients to increased levels of protein as well as the changing nature of the resulting physicochemical. Fermentation is carried out using lactic acid cultures of Lactobacillus casei starter with a concentration of 1%, 3%, and 5% V and nutrients used is ammonium hydrogen phosphate 5% w. In the fermentation process used pieces of 2 mm thickness of chips, 4 mm and 6 mm.The fermentation process is carried out for 72 hours, with the room temperature. From the results obtained: improvement of the highest protein of 3.68% in 2 mm, 5% V variable,% solubility best of 1.63% at 2 mm, 5% V variable, swelling power best of 17.8% in 2 mm, 1% V variable,% carboxylic 0.4% on the largest variables 2 mm ,5% the best tensile strength in noodle products of 0,138 N/mm2 with ratio of 10% MOCAF and 90% of the flour, and pilus expand power of 261,71% on 5% V variable