A quick internet search reveals the following:
About seventeen percent of the AU student body belong to fraternities or sororities. Greek organizations have been a part of American University since 1933. For over 60 years, Greeks have contributed to academic excellence and the strong community spirit on campus. The Greek community provides friendship, growth, and leadership opportunities for the AU students who choose to be members. Many fraternities and sororities also offer community service or academic related activities.
AU Fraternities
Alpha Epsilon Pi
Alpha Sigma Phi
Delta Chi
Delta Tau Delta
Phi Sigma Kappa
Sigma Alpha Mu
Sigma Chi
AU Sororities
Alpha Chi Omega
Alpha Epsilon Phi
Alpha Kappa Alpha
Alpha Nu Omega
Chi Omega
Delta Gamma
Delta Sigma Theta
Lambda Pi Chi
Phi Mu
Phi Sigma Sigma
Sigma Delta Tau
Sigma Gamma Rho
Zeta Phi Beta
Note there is no TKE chapter