The article examines the population life quality as one of the most important indicators that reflect the level of development of any country, and its evaluation. The intricacy of the problem of life quality assessment is due to a large number of indicators on hand. The authors presented the basic theoretical concepts of life quality and methodological approaches to measuring and assessing life quality (objectivist and subjectivist). Particular attention is devoted to one of the main indicators of life quality – Human development index. Presented is the analysis of its calculation by the old technique, which was used until 2010, and by the new one, currently adopted. The main purpose of using the human development index is to draw up the inter-regional ranking of countries with a view to assess the population life quality dynamics and to compare it with other territories. 75 countries with high, average and low values of HDI were chosen for the analysis. The correlation coefficient is counted, proving the linear dependence between final values of the HDI, made by means of the old and the new methods for different countries. Calculation of the Russian Federation HDI is made using the Federal State Statistics Service data. The result differs from the RF HDI in the global HDI ranking presented by the UN report, which could be explained by using statistic data for calculating from different sources.