Export concentration is a fundamental concern, by and large to developing economies where a limited range of products (disproportionately) make export earnings up. Among other objectives, to expand export bases and activities, these countries have attracted a substantial amount of FDI by providing numerous incentives and easing stringent regulations. But little has been done in demonstrating whether FDI helps reduce export concentrations. Using highly disaggregated CEPII's exports data of 67 developing economies for the years 1995 to 2018, this thesis empirically examined the impact of FDI (stock and inflow) on export concentrations (by products and destination markets). I constructed a panel of Herfindahl-Hirschman indices of export concentrations inverse measures of export diversifications for each country in which FDI was modeled as a determinant. And the empirical analysis was accomplished by a Fixed Effects method. Empirical findings show that FDI does significantly and negatively affect overall export concentrations (both by products and destination markets) of host economies under the study, i.e., it promotes export diversifications. As such, attracting FDIs helps host economies combat dependency on a restricted set of export commodities and markets (trade partners).