The purpose of this epidermiological analysis was to evaluate the periodontal status of Korean young adults(twenties) in order to provide detail & baseline data for frequence of periodontal disease. Two hundred and fifty young adults, aged 20-29 years, were selected by random sampling. Dental visity, scaling treatment, education, income, toothbrushing frequence & method were checked, and plaque index(Loe and silness), calculus index(Ramfjord), gingival index(Loe and silness), attached gingival width, perio probing depth, gingival recession were measured. The obtained results were as follows. 1. Average plaque index(1.96), calculus index(1.43), gingival index(1.7) were higher in mandible than maxillar. It was most prevalent in lst molar. 2. Average attached gingival width(4.0mm) was wider in maxillar than mandible. It was most prominent in lateral incisor. 3. Pocket depth(>4mm) was distributed in 42% subject, it was higher in mandible than maxilla and most prevalent in 1st molar. 4. Gingival recession(>1mm) was distributed in 94% subject, it was higher in mandible than maxilla, and most prevalant in canine. 5. According to unpaired t-test, palque index, calculus index, gingival index were not statistically significant in history of scaling treatment, level of eduction and account of income, but were showed statistically significant in histrory of dental clinic.(PB0.05) 6. According to ANOVA test, correlation between tooth-brushing(frequence, method) and gingival index was showed statistically significant.(P<0.05) 7. There was gingival recessionof 87% subject in only one time brushing, 80% subject in two time, and 68% subject in three times. There was gingival recessionof 68% subject in leftright direction tooth brushing, 73% subject in upper-low method and 77% subject in combination method.