The aim of our study is to analyze the effects of inequality of opportunity on internal armed conflicts in developing countries. In a panel of 69 developing countries, over the period 2000–2020 and using the Logit model, we find a positive and significant relationship between inequality of opportunity and the risk of internal armed conflict. The effects are higher in Asia than in Africa. As our results are validated by changing the dependent variable and the estimation technique, and by adding new variables, we recommend, on the one hand, increasing spending on social sectors by promoting decentralization to improve their efficiency. On the other hand, job creation at local level and infrastructure improvements designed to make developing countries more attractive to foreign direct investment.