A bus-line protector preventing the bus-lines within a computer casing from moving around and being damaged by metal components is disclosed. The bus-line protector has a base plate and at least one wing plate, wherein the base plate has at least one notch and at least one fold line. The wing plate is extended from the fold line of the base plate and comprises at least one insert extended from a periphery of the wing plate. After placing the bus-lines on the top surface of the base plate, the wing plate is inclined inwardly at the fold line and covers the base plate. Then, the insert comprising a T-shaped protrusion is securely engaged into the notch of the base plate. As a result, the bus-lines are fixed in location and are thus protected by the bus-line protector of the present invention.