Informal economy size in developing countries, especially in Latin American countries, represents one of the greatest challenges for development, given its relationship with the inequality, the conditions of vulnerability and exclusion of a wide range of the population. The firms, both born and established in informal economy, can be innovative and have the potential to create solutions that have a positively impact well-being of many people in conditions of exclusion, through inclusive innovation processes; However, there are still gaps on how the informal economy agents can participate in dynamic of innovations systems. This makes it difficult to implement strategies and policies that strengthen innovation systems. Therefore, the objective of this work is to propose a conceptual model following the first steps of Agent-based Modeling methodology. This model allows representing the inclusion of informal companies in innovation systems, which will be the basis for future systemic and longitudinal analyses.