The streak-backed canastero (Asthenes wyatti) is a species of bird in the Furnariinae subfamily of the ovenbird family Furnariidae. It is found in Argentina, Bolivia, Colombia, Ecuador, Peru, and Venezuela.

The streak-backed canastero is 16 to 18 cm (6.3 to 7.1 in) long and weighs 17 to 25 g (0.60 to 0.88 oz). The sexes have the same plumage. Adults of the nominate subspecies A. w. wyatti have a narrow buff supercilium on an otherwise grizzled light brown and blackish face. Their crown, nape, back, rump, and uppertail coverts are olive-brown. Their forehead has dark brown flecks that become thin streaks on the crown and nape and wider streaks on the back. Their wings are dark fuscous with rufous edges on the coverts, tawny-rufous edges on the primaries, and rufous bases on the secondaries; the last form a wingband. Their central three pairs of tail feathers are dark fuscous brown with progressively more rufous on the outer webs The rest of their tail feathers are mostly rufous with some dark fuscous on the inner webs. Their chin is tawny-buff, their upper throat light orange-rufous and their lower throat pale brownish gray (both with thin dark brown streaks), their breast light brown with almost invisible dark brown flecks and spots, their belly bright tawny-buff, and their flanks and undertail coverts rufescent buff.

The other subspecies of the streak-backed canastero differ from the nominate and each other thus:

A. w. sanctaemartae: wider but less contrasting streaks on the back, darker orange throat, dingy grayish buff underparts

A. w. phelpsi: light brown underparts and dark chestnut-brown instead of rufous on outer tail feathers

A. w. mucuchiesi: less brownish upperparts with grayer edges to the streaks

A. w. aequatorialis: grayer or more rufous upperparts and blacker tail

A. w. azuay: buffier underparts than aequatorialis; almost entirely rufous wings

A. w. graminicola: tawny underparts with only a hint of streaks

A. w. sclateri: pale gray-brown upperparts with rufous-edged blackish streaks, dark brown wing coverts with rufous-chestnut edges, base of flight feathers bright rufous and the rest brown with rufescent edges, central tail feathers dark gray-brown and the rest dark fuscous with progressively more rufous at the ends, whitish throat with faint pale rufous center, tawny-buff underparts

A. w. punensis: darker and grayer upperparts with less streaking than sclateri and rufous only at the tail feather tips

A. w. cuchacanchae: paler and more heavily streaked upperparts and paler and less tawny underparts than sclateri, and paler rufous on the flight feathers

A. w. lilloi: slightly darker upperparts than cuchacanchae with a rufescent tinge and heavier streaks, rufous on flight feathers intermediate between cuchacanchae and sclateri

A. w. brunnescens: essentially the same as sclateri

Subspecies A. w. graminicola and A. w. punensis intergrade in the area of Lake Titicaca on the Peru-Bolivia border.