This article applies the method of Shapley-Owen-Shorrocks (SOS) decomposition sequence, championed by Anthony F. Shorrocks, to investigate how economic growth, uneven redistribution of incomes, and the transformation of population compositions might affect the variation of poverty in Taiwan. We can summarize our findings as follows: 1. With regard to the level of poverty, between 1988 and 2006, poverty in Taiwan exhibits an interrelated tendency of three reverse-U shapes tilting toward the right-hand side. 2. Among the poor, the percentage of the unemployed household breadwinners climbs significantly, while the percentage of working poor declines. 3. Even though the growth of income retains its function of reducing poverty, it is less significant as a factor than the unequal redistribution of income is in reducing poverty; the fact that the extent to which different sectors benefit from the growth of income varies raises serious doubt on the presumption of a so-called ”trickling down effect”.