 This is a multi-center, open-label, non-randomized, single-dose, sequential-cohort study in subjects with varying degrees of hepatic impairment, classified according to the Child-Pugh system, who will be matched with normal healthy subjects as controls. The study will be conducted in two phases: Pretreatment and Treatment. The Pretreatment Phase will have two periods: Screening and Baseline. The study will enroll a sufficient number of subjects so that at least 24 subjects complete the study. This will include six subjects with mild hepatic impairment Group 1, six subjects with moderate hepatic impairment Group 2, four to six subjects with severe hepatic impairment Group 3, and eight subjects with normal hepatic function Group 4. Potential study subjects with hepatic impairment Groups 1, 2, and 3 and those with normal hepatic function Group 4 will first be screened for study entry. Group 1, 2, and 3 subjects will be enrolled sequentially into the study first. The Group 4 normal healthy subjects will be enrolled following enrollment of all of the hepatic impairment subjects. Subjects determined to be eligible for the protocol will receive either a 5- or 10-mg single oral dose of lenvatinib on Day 1, depending on their hepatic status. Subjects will be discharged from the unit on Day 17 - 2 days after all study discharge procedures have been completed. 