Some commercial districts attract most of their visitors only during day-time,whileothersatnight-time.Thisdifferenceintimeof population flow may be affected by land use such as mixed-use. This paper aims to analyze the different impacts of mixed land-use on population flow between the diurnal and the nocturnal districts. Onanhourlybasis,thestandardizedvalueofpopulationineach census tally-districts forms distinct patterns in the 24-hour range. Basedonak-meansclusteringwithanhourlylocation-based population dataset collected from smartphone signal in Seoul, we classify census tally-districts in commercial areas into two groups: Diurnal and nocturnal. We introduce a binomial logistic model where a binary indicator is used as the dependent variable for the two groups. A comparison of land-use patterns between the two groups shows some significant differencesasfollows:First,thenocturnalareastendtohave distinctivefeaturesconsistingofvibrantstreetsduetoahigher degree of mixed use. In those areas, the degree of mixed-use is found to be higher. Next, the residential use has a higher impact on the increase of floating population than other uses. These results imply that a proper degree of mixed use attracts morepeopletocommercialdistrictsevenatnight,thereby enhancing the vitality of the streets.