A roll rod device for a vehicle includes a mounting flange mounted to a vehicle body; a housing of a cylindrical shape integrally formed at the mounting flange; a roll rod having a first end coupled to the housing to be slid and moved and a second end on which a bush unit is mounted; and an attenuation unit mounted to the first end of the roll rod and attenuating a vibration and an impact force while being slid and moved, or being compressed and tensioned in an axis direction of the roll rod inside the housing.