The growth and development of the research in the singular perturbation theory in the Department of Mathematics at East China Normal University is reviewed, uncovering historical facts in this research area in China. Some outstanding Chinese scientists, such as QIAN Wei-chang, GUO Yong-huai, QIAN Xue-sen and LIN Jia-qiao, have made pioneer contributions in this area.The Chinese Culture Revolution interrupted the research. In the late 1970s, after the end of the Culture Revolution, the section on research and teaching of differential equations in the department of mathematics of ECNU decided to make the theory and application of singular perturbation as a research direction. In the early 1990s the research is thriving under the efforts of themathematicians in China. After then, however, was a recession period because of the lack of new researchers. But now, as a result of Chinese Government's continuously supporting of scientific researches, and outstanding mathematicians such as Ni Ming-kang have returned from abroad, the research of singular perturbation is becoming active again at our university and inChina.