Licson Lee says to YSITDAlthough Hong Kong’s population density is lower than Singapore’s, it is in fact way higher if you consider that only 23.7% of its land is developed given the mountainous terrain and other factors. Of this, only 76 sq km of land, or 6.8% of the total land area, is developed for residential purposes. An expert estimates that population densities measured at block level in some areas may even exceed 400,000 persons per sq km.at Sat, Sep 10, 2016 7:56 PM