Laetare Sunday is a name formerly often used, and less commonly used today, to denote the fourth Sunday of the season of Lent in the Christian liturgical calendar. It is used predominantly, though not exclusively, by Roman Catholics.

Laetare is a Latin verb meaning "to be joyful."

This same Sunday is also known as Mid-Lent Sunday, or Mi-Careme in French.

In the Roman Catholic Church, priests are given the option to wear rose-colored vestments to Masses held on this day, in place of the purple vestments normally worn during Lent. The Gospel reading for this Sunday recounts the miracle of the loaves and fishes.

This date can fall anywhere between March 1 and April 4.

See also Gaudete Sunday, Mothering Sunday