According to the models of the multinational enterprise tariffs play a fundamental role in determining the pattern of foreign direct investment (FDI). The aim of this paper is to assess the impact of tariffs on the outward stocks of FDI of the European Union (EU). We estimate a model based on the knowledgecapital theory of the multinational enterprise over the period 1995-2008 by using a sample of five EU countries and 24 partner countries. We consider, first, manufacturing sector as a whole and, then, six manufacturing industries defined at the two-digit level of the Nomenclature statistique des activitéś economiques dans la Communauté européenne (NACE) classification. Explanatory variables include an index of applied bilateral tariffs and a dummy to capture the presence of bilateral investment treaties (BITs). A dynamic panel model is estimated through the generalized method of moments estimator, taking also into account the endogeneity of regressors. The results show that the pattern of EU outward FDI is a mix of vertical and horizontal FDI. BITs in force have a significant and positive impact on the outward FDI. The impact of tariffs varies across industries and countries, suggesting the predominance of horizontal FDI in some industries, and the existence of vertical FDI in others.