Ocwinyo was born in Teboke village in Apac District. His father worked in the Uganda Prisons Service and his mother was a housewife. Before joining the Prisons Service his father had served in the King’s African Rifles and had been deployed to Misr (Egypt) towards the end of World War II.
Ocwinyo studied at Aboke Junior Seminary and Lango College, before joining the Institute of Teacher Education at Kyambogo, where he earned a Diploma in Education. He later studied at Makerere University, where he received a Bachelor of Education. Ocwinyo taught at various educational institutions before becoming an editor for Fountain Publishers, Kampala.