This research paper identifies and explores the opinions and attitudes of young people about urban transport. It is the first study on this topic, based on the survey, analysing the mobility choices of young adults (more specifically, Generation Y) in Poland and for countries in Central and Eastern Europe. The aim of the paper is to show their travel behaviour from sustainable mobility perspective. The primary data was obtained through the online survey. The data analysis was held with use of factor analysis and ANOVA. The research results indicated the variables influencing the environmental dimension of sustainable mobility attitudes of young adults in four areas: the ecology-oriented approach to transport, opinions about sharing economy, public car concept and future transport system. The analysis of variance revealed significant differences in the ecology-oriented approach between people born in different decades, between men and women and between people with driving licences and people without them. Those results provide the insights for local authorities and mobility service providers. The recommendations at the end of the paper focus on the need for continuation of research in similar fields.