Kézdiszentlélek is renown mostly for its beautiful church, the medieval pile is considered a monument. The building was erected on the North-Eastern rise of the village, the wall ambient to the presbytery, with its peculiar delineation is unique amongst the similar edifices of Háromszék.
Although, according to the inscription on its South-Western heel the church was built in 1401, most probably it had been erected in the second half of the 15th century rebuilding and expanding the forbearing building. During the next century the gothic style church went through several changes, although some of the ancient buildings entrails, such as the door-frames, the windows and the tabernacle-booth still remain. The interior’s baroque style originates from the 18th century. The church’s adornment is the high altar built in 1685.
The stone missal-table was carved by local craftsmen.
The choir-organ was made in 1902. The presbytery was expanded on both sides in 1980, and recently restored.
The tower, rising to 28 meters gained its current form in the 1770s. According to professionals the castle-wall surrounding the church, with its manikin corner-fortifiers was erected around the end of the 17th century, at the beginning of the 18th. One of the towers houses a permanent exhibition of the parish.