F.O.P.-Cambridge (1897) considered Cupiennius an odd ctenid taxon for having a third tarsal claw and also for carrying the egg sac with the spinnerets, a feature typical of lycosid spiders.

Although the genus Cupiennius is today well diagnosed (Barth and Cordes, 1998; Brescovit and Eickstedt, 1995; Lachmuth et al., 1994), its familial position is still not clarified and modern DNA sequence data (Huber et al. 1993, Piel in Silva Davila 2003) supported the hypothesis, that Cupiennius is rather distant to the true Ctenids.

Polotow et al. (2015) stated: "Our results do not corroborate the position of Cupiennius within Ctenidae and consistently show this genus as sister-group of Lycosidae and Pisauridae".