The purpose of this study was to explore patterns of lifestyle walking behavior among Japanese adults aged 30-49 and to identify their sociodemographic characteristics.A sample of 5,009 was collected from registrants of a social research company. The study was a cross-sectional survey using the Internet. Measured variables were walking behavior in five domains (commuting, working, shopping, exercising and other movement) and sociodemographic characteristics. Hierarchical cluster analysis was utilized to identify walking patterns.Four walking behavior clusters were identified: cluster 1 (N=1,089) walking while commuting, working and shopping; cluster 2 (N=381) walking while commuting; cluster 3 (N=1,257) walking for exercise; cluster 4 (N=1,161) walking while shopping. Cluster 1 had the highest proportion of walkers who met physical activity recommendations. Also it had a high proportion of women who were unmarried, employed, without children, or finished university or graduate school. Cluster 2 showed a high proportion of men who were married, with children, with high household income, or finished university or graduate school, and women who were married, employed, without children, with high household income, or finished university or graduate school. Cluster 3 had a high proportion of women aged 40-49. Cluster 4 showed a low proportion of men with high household income and a high proportion of women who were married, unemployed, or with children.This study indicated that walking behavior patterns in both genders was different depending on marital status, number of children, educational level and household income. In addition, the employment status of women had apparent effects on these patterns.