Caecilia mertensi is a species of caecilian in the family Caeciliidae from South America.

[3] The type locality is imprecise: the holotype was purportedly collected in "Seychelle Isle", but most likely originates from South America.

[3][4] The specific name mertensi honors Robert Mertens, a German zoologist and herpetologist.

[1] The Mato Grosso records are from the Amazon biome or from its transition zone with the Cerrado.

[4] In 2004 it was assessed as "data deficient" for the IUCN Red List of Threatened Species.