The Holy Forty Martyrs of Sebastia Cathedral () is a Greek Orthodox cathedral located in the Old City of Homs, Syria. Dedicated to the Forty Martyrs of Sebaste, the cathedral is the seat of the Greek Orthodox Archbishop of Homs and Dependencies.
A "beautiful church dedicated to the Forty Martyrs" standing in Homs was mentioned by Joos van Ghistele in the 15th century.
By 1914, "a large bell" had been sent from Russia for this church.