Introduction: Cassava (Manihot esculentaCrantz) pulp was increasingly and potential as environmental pollution, this study aimed to determine the optimal condition for increasing protein content of cassava pulp by microbial fermentation under the various condition. Methods: Cassava pulp were fermented with each pure strain of S. cerevisiae or C. Utilis using urea as a Nitrogen (N) source (0, 2, 4, and 8%) for 8 days. Reducing sugar, crude protein, NPN and cell number were measured daily. Results: It was found that significant increase (p__ampersandsignlt;0.05) in the reducing sugar, crude protein and yeast cell of fermented cassava pulp compared to unfermented. C. Utilis fermented cassava pulp increased higher protein content and reduced NPN level compared to S. cerevisiae. Protein and cell number can be increased from 2.59% and 0.59 x 109 cell/g (unfermented) to 33.34% and 5.13 x 109 cell/g, respectively, of which the optimum condition for producing the maximum cell count of C. Utilis was 4% urea and fermented for 4 days. Conclusion: It is suggested that the use of cassava pulp fermented with C. Utilis at 4% urea for 4 days could be optimal to improve total protein by up to 30.55 and 16.13% of true protein which would subsequently as alternative feedstuff for animals.