Rev. Fr. Haik Donikian was born in Bandrma, Turkey, to Armenian parents who had him christened Garo.  After his family emigrated to Kavala, Greece, he attended the American Anatolia College in Salonica, where he received a bachelor's degree.  He continued his education at the Melkonian Educational Institute in Cyprus.

Upon the death of his father, Rev. Fr. Jirayr Avak Kahaba Donikian, Fr. Haik returned to Greece, then settled in Vienna, Austria, where he attended the Business College of Vienna.  He married the Maireni Taschdjian of Vienna, and they had a daughter, Shooshan.  In Austria, Fr. Haik served as a tbir, choirmaster, and deacon for 16 years at the Church of Our Savior in Vienna. 

In 1954, he was ordained a priest by the late Primate of the Diocese of the Armenian Church of America, Archbishop Mampre Calfayan, at the Holy Cross Church of Union City, New Jersey. 

Following his ordination, Fr. Haik served as assistant pastor at the Holy Cross Church in New York City for one year.  Fr. Haik was then appointed pastor at St. Sahag and St. Mesrob Church in Providence, RI, where he served 22 years, from June 1958 to April 1980.

In 1966, His Holiness Vazken I, Catholicos of All Armenians, granted Fr. Haik the right to wear the Pectoral Cross.

Fr. Haik assumed the position of assistant pastor at St. John's Church of Greater Detroit on May 19, 1980.  In 1983 Fr. Haik was elevated to the rank of Archpriest (Avak Khakana).

Along with his parish duties, Fr. Haik has served in the several capacities, including as chairman of the Armenian Choir Association of the Diocese; as a Police Association chaplain in Providence, Rhode Island; and as a member of the State Council of Churches in Providence, Rhode Island.  He also was a member of the Diocesan Council.