The aim of this thesis was to investigate the consumption of food and consumers' food-related behaviour by examining the life styles to determine food-related lifestyle segments in St. Petersburg, Russia and Joensuu, Finland. The study also concentrates on researching consumers' attitudes, interests and opinions in relation to food and eating. The objective was to investigate how people proceed with their shopping, perceive quality and what their purchasing and consumption motives are. A research method was quantitative. All together 412 respondents were interviewed: 212 from St. Petersburg and 200 from Joensuu. Data was analysed with the SPSS Statistics 17.0 programme. Four consumer segments were found, which also differ in socio demographic characteristics. These segments were named: hedonistic, low-involved, traditional and adventurous. In both countries the largest segment was the adventurous food consumer. Respondents from both market show similar consumer behaviour, but some distinctive cultural differences exist. Despite the obvious similarities in findings, national characteristics must be taken into account while evaluating the markets.