Abstract: The mainstream literature attributed the driving factors of structural transformation to the demand- si-de income effect and the supply－side relative price effect，that is，the response of representative consumers   to income and relative price of products shaped the consumption structure，which led to the reallocation of res-ources among the three industries． However，representative consumers under nonhomothetic preference are  not a reasonable substitute for the overall behavior of society． In this regard，this paper introduces urban－ru-ral income distribution into a multi－sectoral growth model，and proposes the mechanism of income disparity  in structural transformation: On the one hand，income disparity produces a heterogeneous consumption structu-re，and the income effect depends on income distribution; On the other hand，the income disparity also affects human capital expenditure，and the level of human capital changes the relative price of products． At the same time，with the introduction of urban and rural income distribution，the theoretical model still has a generalized balanced growth path that satisfies the“Kaldor facts”and the“Kuznets facts”． Finally，the mechanism and pol-icy effects of the two income redistribution measures are analyzed through numerical simulation，and it is foun-d that increasing the proportion of rural population and increasing the per capita income of rural residents have different mechanisms for structural transformation，and the latter has a weaker restraining effect．

Keywords: urban and rural income distribution; structure transformation; income effect; relative price effect