According to economic index theory and consumers preference difference, this paper constructs changeable preference living cost index based on GFT direct utility function, works out and compares stratified CPI in seven income stratified classes in China’s urban residents during 1996—2011, and the results show that there is relatively small difference between each stratified CPI before 2007, however, the difference is significantly enlarged after 2007, that the stratified CPI in the residents with low income is higher than the stratified CPI in the residents with high income, that overall index of CPI of urban residents approximately reflects the situation of living cost change in the stratified classes with “the income a little more than middle class”, however, other stratified residents usually have “distorted sentiment” to overall index of CPI, as a result, the representation of overall index of CPI in urban areas is reduced, thus, the composition of stratified CPI based on different income classes can not only reflect inflation pressure of each stratified class of the residents to keep the authority of CPI but also provide accurate information for governmental scientific decision-making.