How do electoral institutions interact with the ethnic fractionalization in shaping citizens’ attitudes towards their political systems? Using Afrobarometer survey data collected from 15 sub-Saharan African countries, along with contextual variables, this study demonstrates that electoral systems have differential effects on citizens’ attitudes about regime performance in various social contexts. Majoritarian electoral systems are likely to exacerbate the negative effect of ethnic fractionalization on popular trust in political institutions, satisfaction with democracy, and perception of government responsiveness. By contrast, proportional representative (PR) electoral systems tend to mitigate these negative effects. While majoritarian electoral systems emphasize the directness and clarity of the connection between voters and policy-makers, PR systems facilitate the representation of all factions in society. At lower levels of ethnic fractionalization, therefore, majoritarian electoral systems are better for boosting popular support for the political system, whereas at higher levels of ethnic fractionalization, PR systems enjoy an advantage.