Police say the melee on the Cobb County Transit bus occurred Monday afternoon in Kennesaw, about 25 miles northwest of Atlanta.
The Atlanta Journal-Constitution reports that the driver went to the back of the bus to keep the quarrel from escalating, and a woman pulled a knife.
Authorities say other passengers were able to get the knife away from the woman, but police say she grabbed a pen from the bus driver's pocket and stabbed him several times.
The bus driver's condition was not immediately known.
