Agnes Irwin (December 30, 1841 – December 5, 1914) was an American educator, best known as the first dean of Radcliffe College from 1894–1909 and as the principal of the West Penn Square Seminary for Young Ladies in Philadelphia, later renamed, in her honor, the Agnes Irwin School, from 1869-1894. Today, The Agnes Irwin School continues to be a leader in girls' education with 665 girls enrolled in grades PreK-12. The school is currently located in suburban Rosemont, Pennsylvania, 10 miles west of Philadelphia.
She was born in Washington, DC, the daughter of Congressman William Wallace Irwin. Her mother, Sophia Arabella Bache, was born November 14, 1815 at Philadelphia, and died there on March 24, 1904; she was the daughter of Richard Bache, Jr., who served in the Republic of Texas Navy and was elected as a Representative to the Second Texas Legislature in 1847 and Sophia Burrell Dallas, the daughter of Arabella Maria Smith and Alexander J. Dallas, an American statesman who served as the U.S. Treasury Secretary under President James Madison. She was also great-granddaughter of Sarah Franklin Bache and Richard Bache, and more notably she was the great-great-granddaughter of Benjamin Franklin, as well as a grandniece of George Mifflin Dallas, the 11th Vice President of the United States, serving under James K. Polk.
With Sarah Butler (Mrs. Owen J.) Wister, she was the editor of Worthy Women of Our First Century (1877).
She died of pneumonia in Philadelphia in 1914.
She was the subject of a 1934 biography by Agnes Repplier.