Whether at home or abroad, the status of women is constantly rising, which is true that women's own efforts, but the affirmative action around the world has also played an important role. The affirmative action movement of higher education aims to ease the problem of discrimination in higher education, increase the number of vulnerable students, build a diverse student group, and realize equal rights in the field of education. However, in practice, the gender-based admission policy of higher education has been criticized, and the public has received mixed praise and criticism. In the face of these arguments and challenges, the Supreme Court's decision has also made different understandings and interpretations, which has aroused controversy and doubts among policy makers and scholars. Critics have noted that the preference policy deliberately lowers the demands for women, which creates reverse discrimination against male applicants with higher scores. Supporters argue that treatment is to achieve real gender equality. Therefore, it is necessary to reflect on the equality and justice of gender equality. This paper mainly describes the brief history of gender equality in American education, studies the criterion of gender. It also discusses the legitimacy of gender equality measures in higher education, and the effect of gender equality in American higher education, which promotes women's social status to weaken or eliminate gender discrimination. It is through the above historical narration, basic concept clarification, goal certification and effect proof that this paper shows a defense theory of the gender equality movement in the field of American education, which gives a strong defense to this important milestone in the history of the feminist movement.Through analysis, this paper finds that the gender equality movement in the field of education in the United States is of great significance for safeguarding women's rights and safeguarding the justice of the United States Constitution. In recent years, the status of women in the field of education has been significantly improved, but there are still many problems in the judicial practice of women's rights, and the conservative forces still occupy the mainstream position in the courts. There is still a long way to go for equal rights in female education, which needs to be further upheld and defended to promote the actual implementation of equity and justice.