Abstract: The subject of this article is the tax systems of two Latin American countries, Colombia and Chile. The main purpose of the article is to analyze the influence of tax measures on private investment in these countries. Main corporate taxes and contributions in Colombia and Chile and key corporate tax reforms in the past decades were described. The assessment of tax effects on private investment was given. The main scientific methods that are used in the article are systems, logical and comparative legal analyses. The scientific and practical novelty of the received results is that they allow to expand the database on tax measures to promote private investment. It was revealed that these countries apply various tax incentives that have unequal effectiveness on promoting investment. Moreover, it was concluded that taxation in Chile and Colombia is not the main factor that determines gross capital formation dynamics.