It was approximately estimated that loss of protein of under-milled rice was about 8-10%; of medium-milled rice, about 15-20%; and of well-milled rice, more than 20%. The degree of bran removal was the main factor which affected loss of protein during milling. It influenced the protein contents of the bran removed during milling. The degree of bran removal was affected by physical dimensions of rice grains, the time duration, the type of whitening machine used as well as the clearance between the cone surface and the rubber brakes.