The purpose of this study was to develop a large representative data base of market information for jeans apparel. This study was to observe consumer buying behavior and to determine the market share of various brands depending on several variables such as age and distribution regions. This study also analyzed the major factors in purchasing jeans for 17-29 age groups. The 660 questionnaires were distributed and 618 reliable ones were used for statistical analysis. A SAS statistical package including frequency table, Chi-square test, factor analysis, analysis of variance(ANOVA), Duncan`s multiple range test was used. The results of this study showed that consumer possessed about 6 pairs of jeans and bought about 3 pairs of jeans per year. The most recently purchased brand was Nix. Lots of brands were statistically significant at the segmented three age groups and in the five different distribution regions. The most popular type of design was the basic style. The result of factor analysis indicated 4 factors(quality/comfort, famous brand/fashion, mood/extrinsic attitude, economy). The result of ANOVA represented that three factors among them have influenced on the preferred design types.