Houston police say 44-year-old Ana Lilia Trujillo told investigators the man was attacking her and she acted in self-defense.
Trujillo was charged with murder in the Sunday stabbing death. In a statement Monday, the University of Houston identified the 59-year-old man killed at a luxury high-rise condominium as Alf Stefan Andersson, a research professor in the university's biology and biochemistry department.
Police say officers answering an assault report found Andersson's body on the floor with multiple stab wounds to the head.
Trujillo remained jailed Monday on $100,000 bail and had no attorney yet.