Social capital is a key factor in corporate sustainability in the ecosystem era. Analysis of the theoretical background reveals that social capital can function at all levels of economy – from the individual to the state. Therefore, social capitalis on the one hand an independent resource generating income. On the other hand, social capital provides access to the ecosystem actors’ resources.Oftentimes stakeholders underestimate social capital because of its intrinsic “public good” quality and limit investment in it. The ecosystem social capital structure includes several dimensions. The elements of each dimension are applied to strengthen the performance of corporate sustainability indicators.