A popular festival, namely Annai Velankani Festival is observed in the church ground of Velankanni, situated at Nagapatttinam, which is almost three hundred and fifty kilometers away from the beautiful city of Chennai. This eleven day long festival is dedicated to `Our Lady of Health` , better known as `Annai Velankanni Matha`. Feast, merry making are key ingredients along with huge procession of flag bearers. This is followed by the ceremony of flag hoisting on the church ground and thus begin the festival festivity. Myriads of devotees and tourists gather here from all over the country to become a part of this Annai Velankani Festival. The first day of the festival starts with holy prayer, blessings, rightly follows by a special holy mass in Tamil language.

Thousands of pilgrims and devotees from all over the country are expected to attend the first day prayer, blessing and holy mass in Tamil. At the main shrine of the church, people who are sick and suffering from diseases, tries to acquire holy blessings from "Our Lady of Health". Apart from holy mass, special `high mass` are also organized in varied languages like Tamil, Marathi, English, Konkani, Malayalam, Telugu and Hindu during the Annai Velankani Festival. These mass starts in the morning and lasts till evening. However, the holy mass is held at 6 `o` clock in the morning at `Our Lady`s Tank`. The festival ends with feting the birthday of `Blessed Mother Shrine`. To accommodate such a huge gatherings, the police provide special facilities. Transport, sanitation, protected drinking water supply are given due emphasis. The Tamil Nadu State Transport Corporation and private operators organize exclusive bus services connecting numerous parts of the Tamil Nadu state.