The Syro-Malabar Catholic Church[16] (Syriac: ܥܸܕܬܵܐ ܩܵܬܘܿܠܝܼܩܝܼ ܕܡܲܠܲܒܵܪ ܣܘܼܪܝܵܝܵܐ) is an Eastern Catholic church based in Kerala, India. The Syro-Malabar Church is an autonomous (sui iuris) particular church in full communion with the pope and the worldwide Catholic Church, including the Latin Church and the 22 other Eastern Catholic churches, with self-governance under the Code of Canons of the Eastern Churches (CCEO). The Church is headed by the Major Archbishop of the Syro-Malabar, currently George Alencherry. The Syro-Malabar Synod of Bishops canonically convoked and presided over by the Major Archbishop constitutes the supreme authority of the Church. The Major Archiepiscopal Curia of the Church is based in Kakkanad, Kochi.[17] Syro-Malabar is a prefix reflecting the church's use of the East Syriac Rite liturgy and origins in Malabar (modern Kerala). The name has been in usage in official Vatican documents since the nineteenth century.[18]

The Syro-Malabar Church is primarily based in India; with 5 metropolitan archeparchies and 10 suffragan eparchies in Kerala, there are 17 eparchies in other parts of India, and 4 eparchies outside India. It is the largest of the Saint Thomas Christians communities with a population of 2.35 million in Kerala as per the 2011 Kerala state census[14] and 4.25 million worldwide as estimated in the 2016 Annuario Pontificio.[13] It is the third largest sui juris church in the Catholic Church communion and the second largest Eastern Catholic church after the Ukrainian Greek Catholic Church.[19]

The church traces its origins to the evangelistic activity of Thomas the Apostle in the 1st century.[20][21][22][23] The earliest recorded organised Christian presence in India dates to the 4th century, when Persian missionaries of the East Syriac Rite tradition, members of what later became the Church of the East, established themselves in modern-day Kerala and Sri Lanka.[24][25][26][27] The Church of the East shared communion within the Great Church until the Council of Ephesus in the 5th century, separating primarily over differences in Christology and due to political reasons. The Syro-Malabar Church employs a variant of the East Syriac Rite, which dates back to 3rd century Edessa, Upper Mesopotamia.[28] As such it is a part of Syriac Christianity by liturgy and heritage.[29]