The aim of this research is to study of pH, population and to determine the diameter of clear zone lactic bacteria on Escherchia coli isolasted form corn waste silage with addition of different corn flour. The design used completely randomized of factorial using 3 x 3. Factor A was the composition of substrate that is : A1 : 100% corn feel + 0% corn straw, A2 : 50% corn feel + 50% corn straw, A3 : % corn feel + 100% corn straw. Factor B was the addition of corn flour, namely : B1: 0%, B2 : 5 % and B3 : 10%. The results showed the not interaction (P>0.05) between factor material used for pH decrease, lactic acid bacteria population and the clear zone diameter on Escherchia coli. The conclusion that silage with addition of corn straw 100% is the best treatment because it can reduce pH, increase the number of BAL population and the diameter of the clear zone.