The Merya people (; also Merä) were an ancient Finno-Ugric people who lived in the regions of modern Russian cities of Rostov, Kostroma, Jaroslavl and Vladimir. They were an old and important culture which is shown in the numerous archaeological finds in those areas.

There is an opinion that Merja is a west branch of Mari people since Merya is Russian transcription of the existing self-name of west Maris Мäрӹ (Märӛ). All Merya toponimy is translated on base of Mari language. Moreover, Russian chronicle "Kazanskaya Istoriya" mentions Cheremis people (Mari) as aborigens of Rostov.

The Merya language was a Finnic language, related to the languages spoken by other tribes in the surrounding larger region, such as the Mari, the Mordvins, the Meshchera and the Veps, although its exact position within the broader Finno-Ugric language group remains debatable.
They are mentioned by the 6th century Gothic scholar Jordanes as the Merens and later by the Russian chronicles. Soviet archaeologists believed that the capital of the Merya was the site of Sarskoe Gorodishche to the south of Rostov. They were assimiliated by the Slavs. However, the Merya culture was also assimilated in those regions that were initially inhabited by Merya. Sacred woods and stones, worshipped by Merya, were part of local traditional feasts for much longer than the similar Slavic sacred places in the west regions of modern Russia.