Palaeophis was named by Owen (1841) [Sepkoski's age data: K Maes T Eo-m-l Sepkoski's reference number: 505]. It is not extant. Its type is Palaeophis toliapicus. It is the type genus of Palaeophidae. It was considered monophyletic by Bajpai and Head (2008).

It was assigned to Ophidia by Owen (1842), d'Orbigny (1849), Cope (1868) and Cope (1872); to Palaeophidae by Hay (1902), Hay (1930), Kuhn (1966) and Holman (1982); to Palaeopheidae by Lydekker (1888), Weems (1985) and Holman and Case (1988); to Squamata by Sepkoski (2002); to Palaeopheinae by Holman et al. (1991), Parmley and Reed (2003), Parmley and DeVore (2005) and Bajpai and Head (2008); to Palaeophiinae by Rage et al. (2003), Snetkov and Bannikov (2010), Snetkov (2011), Zvonok and Snetkov (2012), Kristensen et al. (2012) and Houssaye et al. (2013); and to Palaeophiidae by Rage et al. (2008), Georgalis et al. (2020) and Georgalis et al. (2021).