The best interest of the child stands as an important and fundamental principle of the African Charter on the Rights and Welfare of the Child. The charter’s content is determined and expanded upon by the African Committee of Experts on the Rights and Welfare of the Child through its dual status as a monitoring body for the implementation and as the recipient of the principle. The Committee thus contributes to the promotion and protection of children’s rights. It is therefore important, through this study, to try to answer the question: what is the content of the principle of the best interest of the child under the law developed by the Committee? Indeed, by using the doctrinal approach to legal analysis, it has been shown that the Committee understands this principle in three dimensions. First, it is a principle to be guaranteed in any decision or action taken by the state regarding children. Second, it is an obligation imposed on all persons, authorities and officials in relation to children. Finally, it is the primary consideration and the ultimate result to be achieved. In conclusion, the Committee’s approach is a continuation of the content of its General Comment No. 14 on the best interest of the child. This is to be considered a fundamental right, a general principle of interpretation and a procedural rule.