Santa Maria in Aquiro is a church in Rome, Italy. It is dedicated to Mary, mother of Jesus, and is located on Piazza Capranica.
The church is ancient – it was restored by Pope Gregory III in the VIII century, and thus must have existed before then. One theory is that it was the titulus Equitii, though San Martino ai Monti is a more likely candidate. It is also referred to as Santa Maria della Visitazione, notably by Pope Urban VI in 1389. The origins of the name are nebulous; most attribute it to a corruption of the term a Cyro, perhaps referring in early days to a neighborhood resident. According to another theory Acyro refers to a curruption of the Latin word "circus", a stadium for horse racing, which was located in the vicinity. In 1540 Pope Paul III granted the church to the Confraternity of Orphans, and it was restored in 1588.