Paectes sinuosa is a moth in the family Euteliidae first described by Michael G. Pogue in 2013.

It is found in the Brazilian states of Goiás and São Paulo, north-western Paraguay and the Argentine province of Tucumán.

The costal area of the forewings is dark gray with a few white scales forming short dashes along the costa, especially from the postmedial band to just below the apex.

The larvae have been reared from Schinus terebinthifolius and Lithraea molleoides.

The specific name is derived from the Latin sinuo (meaning bend) and refers to the sinuate free saccular extension of the male genitalia.