This paper investigates the possibility of productivity difference between exporting and non-exporting companies. As a base of econometric studies those conducts hypothesis that exporting companies are more productive than non-exporting are reviewed. Paper finds that there is an effect of companies' export activities on labour productivity growth. On the other hand, previous empirical studies show that exporting does not necessarily improve productivity. This paper examines the relationship between export status and productivity growth, using as an example Latvian manufacturing companies data for the period 2000-2009.