ABSTRACT: Mayonnaise is probably one of the most widely used sauces worldwide. The oil content of traditionally mayonnaise is more than 65%. Fat has a role in creating viscosity, color and texture but might cause many diseases and disorders in human. In this study the influence of modified wheat bran as a fat replacer on the rheological properties of low fat mayonnaise was studied and compared to a blank sample containing starch. Low fat mayonnaise samples containing different amount of modified wheat bran (1, 2 and 3%) and blank were produced. The rheological analysis comprising the evaluation of flow properties and oscillatory tests were carried out by Rheometer. The results of flow curves showed that all the mayonnaise samples exhibited nonnewtonian, pseudoplastic behavior which fitted by Herschel-bulkley model and the factors related to this model were specified in the samples and blank. Storage and loss modulus obtained by the frequency sweep measurement classified mayonnaise samples into weak gels. The results showed that flow properties of mayonnaise samples depended on shear rate. The results indicated that separation between two phases of emulsion didn’t occurred and all the samples were stable. The sample containing 1% modified wheat bran was behaving most similar to the blank and due to the best appropriate ratio between cellulose and starch was selected as the superior sample.