The purpose of this study was to evaluate the bacterial adherence on e-PTFE membrane immersed in whole saliva from subjects with different periodontal status. Experiment involved 3 subject groups: 5 persons with healthy periodontium(probing depth below 3mm and no signs of gingival inflammation including bleeding on probing), 10 patients with gingivitis(probing depth below 3mm and apparent signs of gingival inflammation), and 10 patients with advanced periodontitis(probing depth over 7mm and apparent signs of gingival inflammation). Each disease group was included before and after scaling and root planing treatment. After obtaining whole saliva from each subject, e-PTFE membrane(Gore-Tex periodontal membrane : $GTPM^{(R)}$, W.L. Gore & Associates, Flagstaff, USA) specimens were immersed at room temperature in the saliva aliqouts for 1, 3, 7 days. The weight between pre - and post - immersion in saliva was measured with the analytical balance and the difference was recorded. The specimens were processed for SEM observation. The bacterial adherence on the membrane specimens was evaluated using the scanning electron microscope images. The obtained results were as follows : 1. There was no difference in the weight of bacteria adherent to e-PTFE membrane specimens according to the periodontal status and the immersion periods. 2. As the exposure time to saliva increased, the bacterial adherence to the membrane specimen significantly increased in all groups(P<0.005). 3. As the severity of periodontal disease increased, the bacterial adherence to the membrane specimens significantly increased(p<0.001). 4. After scaling and root planing, the bacterial adherence to the membrane specimens significantly decreased in gingivitis and periodontitis patient group(P<0.001). These results suggest that bacterial contamination on exposed barrier membrane surface be reduced through improvement of periodontal status and oral health environment before and after GTR procedure for the successful outcome.