The International Council of Universities of Saint Thomas Aquinas (Spanish: Consejo Internacional de Universidades Santo Tomás de Aquino) is a world-wide network of universities inspired by the thought of St. Thomas Aquinas.

This takes the form of increasing the interchange between students and professors, the development of joint plans between the various institutions and the sharing of information and programs.

ICUSTA grew out of a meeting in 1993 between representatives of the University of St. Thomas (Houston) and Universidad Santo Tomás, Chile.

They were soon joined by the Pontifical University of Saint Thomas Aquinas, Angelicum in Rome, and the Universidad Santo Tomás, Colombia.

The later meetings were in Manila, in 1997; in Fredericton, New Brunswick, Canada, in 1999; in Rome, in 2001; in Mar del Plata, Argentina, in 2003; and in Barcelona, Spain, in 2005, Australian Catholic University in Melbourne, Australia (2007), and Mary Immaculate College in Limerick, Ireland (2009).