The authors of the paper analyse the aspects of subjective well-being in different age groups of Russian people, with focus on the study of subjective well-being in preretirement age. The results of the national telephone survey conducted by Institute of Social Analysis and Forecasting, RANEPA in 2021 demonstrate that respondents at age 56-65 are the most vulnerable social group in the country. The preretirement age can be called the most disadvantaged age in Russia, although it is traditionally perceived within the administrative system as an unproblematic category of citizens, characterized by a steady demand for stability, predictable behavior and formed attitudes. In answers to the question "In general, how do you assess your life today - as good, rather good, rather bad, or bad?" people of preretirement and early retirement age are more likely than other respondents to choose the variants "bad" or "rather bad" (42% of respondents, in comparison with sample average of 28%). The article attempts to identify the causes of this phenomenon as well as the main factors affecting subjective well-being in the "third age". The authors conclude that changes in social status, i.e. foremost retirement, family changes (children leaving the parental home) and changes in family support networks, physical discomfort, are the main factors for transformation in subjective well-being experience. As a result, there is a decline in the emotional state, a lack of expectations for the future and anxiety state, which can lead to social exclusion. The article was written on the basis of the RANEPA state assignment research programme.