The present study investigates the possible causes of negative attitudes towards use of the Angolan ‘’national languages’’ in Lobito. The study aims at looking at the implications of negative attitudes towards the use of national languages in terms of social, economic and political exclusions of people who cannot communicate in Portuguese language as the main medium of instructions and social mobility. To collect data, we used a semi-structured interview at Complexo Escolar BGN 2012 Evangélico da Canata- Lobito, where (2) two school administratives were selected and (9) nine teachers from different schools in Lobito. The participants were originally from different ethno-linguistic groups (Ovimbundu, Mbundu, Bakongo, etc). The findings show that linguistic heterogeneity creates social and cultural stigmatisation that lead to marginalisation and exclusion. The marginalizations and stigmatizations are associated to lack of prestige and the market value of ‘’ national languages.