The first mention of the Diaconia di Santo Stefano dates back to 1296, when the municipality of Bedizzole held full ownership and patronage rights, covering all expenses. It was also reconsecrated on 13 December 1506 by Monsignor Marco Saracco, Archbishop of Lepanto and vicar of Bishop Paolo Zane. The church had been enlarged with three new chapels: St Stephen in the centre and the Holy Sacrament of Saints Fabian, Sebastian and Roch on either side. The new archpriest, the Reverend Lelio Emigli (Borgo S. Giacomo, 1684 – Bedizzole, 7 July 1770), wanted to build a new church as the old Diaconia was cramped and could no longer meet the needs of the faithful.
On 28 December 1720, the local council decided almost unanimously to build a new church. Construction began on 8 May 1721, the feast day of the patron saints Ermolao and Acacio. On 21 April 1760, His Excellency, Bishop Giovanni Molin, consecrated this church and its monumental altar. The Baroque façade has two tiers featuring statues of saints, as well as a recent portal adorned with a statue of St Stephen by Alessandro Calegari.
The church was designed by Antonio Spazzi, a distinguished member of a family of master builders, plasterers and designers who were active from the 17th to the 18th century. The statues on the façade were created by Alessandro and Gelfino Calegari.