The first joint Armenian Apostolic and Protestant service was held in 1883 at the First Congregational Church of Fresno.

[4] Subsequently, joint Armenian rite services were held in a rented church by Father Aharon Melkonian.

[4] By 1899, the membership of the parish reached 150 and a general meeting decided to build a separate church.

[4] On April 1, 1900, the Holy Trinity Church was established at the corner of F and Monterey Streets.

The construction of the church, a simple wooden structure, was completed in six months and consecration took place on October 1, 1900.

The church was designated as the cathedral of the diocese, while Bishop Karekin Khachdourian as Primate, who served as pastor until 1933.

[4] In 1933, after the murder of Leon Tourian, the primate of the Eastern Diocese, in New York City by a group of Dashnaks, a pro-Soviet group broke away from the pro-Dashnak Holy Trinity Church and formed St Paul's Church[6] in 1939 under the jurisdiction of the Mother See of Holy Etchmiadzin.

[2] The church has a basement, main floor and gallery level with a total of 12,250 sq ft (1,138 m2).