The paper focuses on the research of structural changes of national economy, which is stated as one of the structural reform features, and their evaluation of economic growth. As a result of examining the basic theoretical guidelines of structural changes of national economy in economic literature and applying an econometric approach, a model of Latvian economy is developed. The model is based on the statistical data of the Republic of Latvia for the last twenty years. It describes a correlation between the structural changes of national economy and economic growth of Latvia during the period under consideration. According to the results of the study, the economy of Latvia during the last twenty years was driven by the tertiary sector – the services had significant impact on the economic growth of Latvia.