The exploitation and export of crude oil is the foundation of the economy of many countries. Such a dependence may be the reason for the emergence of a set of destructive economic phenomena known as „Dutch disease”. This phenomenon is described, however, for the period in which oil prices have increased or were maintained at a high level. The description of the effects of the drop in oil prices, which appeared in mid-2014, is missing for the economies of these countries. The aim of this study is to at least partially fill that gap. The subject of the analysis was the impact of oil price changes on the Russian (RTS), Brazilian (BOVESPA) and Norwegian (OSEAX) stock exchange index level during the period from the beginning of July 2014 (moment of the start of the downtrend in oil prices) to the end of June 2017. This analysis used an econometric model built in accordance with the Engel-Granger methodology. The results of this analysis showed that the impact of oil prices on financial markets of crude oil exporter countries in the period was very varied. That impact was most visible in the case of Russia, somewhat weaker in the case of Brazil (in both cases, the fall in oil prices affected the value of the index). That impact it was not determined in the case of Norway