The surname Merenda is diffused across much of central and southern Italy. It is found mainly in the provinces of Rome and Latina, Caserta and Naples, Potenza, Cosenza, Catanzaro and Reggio Calabria, as well as in the province of Lecce and in Sicily, especially in the province of Messina.

The variant Merenna, extremely rare, shows family cores in the provinces of Latina and Cosenza. Merendini appears to be practically unique, while Merendino is clearly Sicilian, with the greatest presence in the provinces of Palermo, Catania and Messina. For its part, Merennino, also very rare, is located in the province of Catania.

All these surnames would derive, directly or through diminutives and dialect adaptations, from the ancient Latin name Merenda. A testimony of this name appears in the Factorum dictorumque memorabilium libri of Valerius Maximus, where mention is made of Titus Antonius Merenda (T. Antonius Merenda), one of the decemvirs who, together with Appius Claudius, was expelled from Rome after being accused of aspiring to tyranny.

The surname would therefore have a patronymic origin, linked to an ancient personal name of Latin tradition.