Cabanis's spinetail (Synallaxis cabanisi) is a species of bird in the Furnariinae subfamily of the ovenbird family Furnariidae.

Adults of the nominate subspecies have a faint ochraceous chestnut streak behind the eye and a grayish white malar region on an otherwise sooty gray-brown face.

Their underparts are mostly brownish gray with a slightly paler belly and a faint brown tinge on the flanks.

Subspecies S. c. fulviventris is smaller than the nominate, with a whiter throat and much paler underparts; their breast is tawny-olive and the center of their belly is buff.

Subspecies S. c. fulviventris is found in the northern Bolivian departments of La Paz, Beni, and Cochabamba.

[8][10] A disjunct population discovered in 1997 in west-central Brazil is currently (2023) assigned to the nominate subspecies but the 2013 publication suggests it belongs in the group of species related to the rufous-capped spinetail.

It is thought to feed on arthropods that it gleans from foliage and small branches, staying about 1 to 2 m (3 to 7 ft) above the ground.

"The primary threat to this species is accelerating deforestation in the Amazon Basin, as habitat is converted for cattle pastures and agricultural fields.