The objective of this article is to offer empirical evidence regarding the behaviour of the exports and relative prices of agricultural and food products from South America between 1900 and 1950. These were years of intense turbulence, which profoundly affected the countries of the region, generating a deep pessimism concerning the potentiality of the export-led development model. This study offers a new quantitative base to analyse the evolution of exports of agrifood products from South America between 1900 and 1938. The paper also offers a series for the evolution of the terms of trade in the region which takes into account in its construction, for the first time, the relative weights of South American exports of the distinct agricultural products.