Woodrow Tracy Harrelson is born in Midland, Texas to Charles Voyde Harrelson and Diane Lou Oswald. The second of three children, he has two older brothers named Brett and Jordan. In 1979, his father is convicted of killing a federal judge and spends the rest of his life in prison. At seven years old, his parents divorce and the family moves to Lebanon, Ohio where he grows up. On his father being a contract killer:
I was 11 or 12 when I heard his name mentioned on a car radio. I was in the car waiting for a lady who was picking me up from school, helping my mum, and anyway I was listening to the radio and it was talking about Charles V Harrelson and his trial for murder and blah blah blah blah and I’m sitting there thinking there can’t be another Charles V Harrelson. I mean, that’s my dad! It was a wild realisation. Then the woman got in the car and saw my face and realised something was up. She was a very kind lady.