This study was undertaken to examine the protein content of GCF and serum from noraml population in order to standardize the sample loading on SDS/PAGE gels. The resulats were as follows ; 1. The protein concentration of serum was not different between normal group and diseased group. 2. In GCF, the bands of lower molecular weight than albumin were heavily stained, but in serum, the protein bands of higher molecalar weight were found. 3. The profile of protein in normal GCF was characterized by heavily staining bands at 77, 66, 55, 26 KDa corresponding to the positions of transferrin, albumin, heavy and light chains of Ig G. Also 47, 37 KDa nonplasma proteins were found.