This study combines space syntax measures and GIS-based built environment variables for an analysis of pedestrian walking volume using the walking survey data for 10,000 locations across the city of Seoul. The results indicate that two syntactic variables of global integration and control show statistically significant associations with the average walking volume for weekdays in Seoul. Global integration measure shows a statistical significance in residential zone, but it did not show any association with walking volume in commercial zone. On the other hand, control value shows a statistical significance in commercial zone, but it did not show any association with walking volume in residential zone. Of built environment variables, statistically significant variables are net employment density and net commercial land use density variables. Accessibility measures to public transportation and urban design characteristics show statistically significant association with pedestrian walking volume. This study concludes that combining space syntax with GIS-based built environment measures has a great potential for analyzing pedestrian walking activities.