Indonesian Journal of Dentistry 2006; Edisi Khusus KPPIKG XIV: 427-430Lip sucking occurred usually on lower lip and probably caused by psychological or environment factor and mostly found on school ages children. Correcting this abnormal habit as early as possible will gave positive correction to malocclusion Practicing myofunctional therapy gradually will eliminate the abnormal habit. ln this report lip sucking bad habit was treated with lip bumper and the severity of this bad habit was decreased in six months.