Studies of the transesterification reaction of vegetable oils are of key importance in the development of a country's national economy. In Latvia, the use of ethanol instead of methanol should enable the domestic raw material base to be extended, and the product would be a fully renewable resource. It is expected that through research, the rapeseed oil ethyl ester (REE) extraction process can be optimized to achieve significant savings of energy resources and raw materials, thereby reducing the end product cost. The decrease in the price of biodiesel would encourage consumer interest and demand, ensuring the development of domestic resources and production to meet transportation requirements. To determine suitable reaction conditions for the extraction of REE (rapeseed oil ethyl esters) from rapeseed oil produced in Latvia, a series of experiments was conducted, using conditions characteristic of industrial processes. The main variables were the concentration of KOH (0.5 - 2.5 weight % of oil), the molar ratio of ethanol to oil (4.0 - 8 moles), reaction temperature (20 - 90oC) and reaction time (2 - 180 minutes). It has been determined that by increasing the molar proportion of ethanol to rapeseed oil from 4.0 to 8.0 moles, the time to reaching equilibrium is shortened, while the REE yield increases by ~4%. When the KOH concentration is increased from 0.5 to 2.5 wt % of rapeseed oil and the reaction temperature is raised from 20 to 80oC, the time to equilibrium is reduced and the REE yield increases by ~1%. For implementation of batch processes, the preferred reaction temperature is 20oC, the molar ratio ethanol is 7 moles and the KOH concentration is 1.5%. However, when using continuous processes, the reaction would be more efficient at a higher temperature with lower quantities of catalyst and ethanol.