The victim, identified as Vanesa P.R., 21, was working Tuesday in a restaurant in the northern city of Trinidad when she had an argument with her boyfriend, who then attacked her with a knife, the online edition of the daily La Razon reported Wednesday.
The attacker, 22, stabbed the woman to death in front of passers-by, who clustered around to watch the attack but did not intervene.
The director of the FELCV anti-violence force, Claudia Romero, told the newspaper's digital edition that the murderer, who tried to kill himself after the attack, is in police custody and "once he improves, the attorney general's Office will determine" if it will take a statement from him.
The prosecutor of the Trinidad district, Wilma Blazz, said that if the witnesses had intervened, "perhaps the life of the young woman would have been saved".
According to UN figures, Bolivia is the Latin American country with the highest rate of physical violence against women.