Existing research mainly examined the urban scaling laws of social inequality based on income variable. Other forms of socio-spatial inequalities and their relationship with population size have not been well understood. Because of the powerful ability of human mobility in revealing socio-spatial inequality and the availability of data sources, this study extends the literature by introduced three types of mobility indicators (i.e., number of activity points, radius of gyration and self-containment). The results show that different characterisation of inequality present different spatial patterns and lead to different scaling laws. Overall, the inequalities in terms of the examined mobility dimensions don’t scale super-linearly with the population size, suggesting the complex nature of urban systems and the social phenomenon.