Abstract: Based on the dynamic monitoring data of Beijing city's floating population in 2012 collected by the State Family Planning Commission, the paper probes into the influence of income on the subjective well-being for this particular group of people. The research unveils the fact that income, whether be personal income or family income, exerts great influence on subjective well-being when population features are taken as the control variable. So raising income is to enhance the sense of happiness for floating people. Income is a key but not the mere factor for subjective well-being. Besides income, other factors such as sex, age, education, marriage, etc. also contribute to subjective well-being.