The capitalist globalization phenomenon restructures global hierarchies, transcending the frame of National States in a new system with multi-scale character. In this scenario, the urban spaces emerge as strategic places, as crucial points of political, cultural and economic interactions to global trends, as well of expression of systemic exclusion, oppression and injustice. Differentiated both by its demographic concentration and by the highly intense phenomena it congregates in its territory, megacities in the context of globalization are affected by the fast and cyclic character of global flows that compress its gigantic spaces and populations. The globalization movement both trespasses and involves the megacities in the Global South, conforming urban conglomerates with intense dynamics and contradictions. By observing the urban phenomenon in the Global South, this dissertation proposes an analytical focus on African megacities, with a special focus on Lagos, Nigeria. From a critical urban theory perspective and the perception of the urban space as a malleable site, in close relation with historically specific relations of social power, this dissertation discusses the ways in which this megacity presents itself before the spatial dynamism proposed by globalization.