Officers responded to the shooting outside TKO Sports Bar and Grill in Laredo at around 2 a.m.
Laredo police found three men had been shot during a fight.
Two of the men, ages 21 and 25, died at the scene, while the third man, who was 21 years old, died at a local hospital, police said.
Authorities have not released the names of the three victims. No arrests have been made in the case.