Dicraeosaurus was named by Janensch (1914). It is the type genus of Dicraeosaurinae.

It was assigned to Sauropoda by Janensch (1914); to Morosauridae by Lull (1924); to Cetiosauridae by Tatarinov (1964); to Atlantosauridae by Charig (1967); to Titanosauridae by Romer (1966) and Dong (1998); to Dicraeosaurinae by Romer (1956), Steel (1970), Swinton (1970), Kurzanov and Bannikov (1983), Kurzanov and Bannikov (1983), McIntosh (1990), McIntosh (1990), McIntosh (1997) and Salgado (1999); to Diplodocidae by Nopcsa (1928), Berman and McIntosh (1978), Charig (1980), Carroll (1988), Calvo and Salgado (1995), Jacobs et al. (1996) and McIntosh (2005); to Diplodocoidea by Xing et al. (2015); to Dicraeosauridae by Xu et al. (2018), Gallina et al. (2019) and Mannion et al. (2019); and to Dicraeosauridae by Huene (1927), Huene (1929), Molnar (1980), Bonaparte (1986), Bonaparte (1986), Bonaparte (1986), Salgado and Bonaparte (1991), Salgado and Calvo (1992), Salgado (1993), Upchurch (1995), Upchurch (1995), Hunt et al. (1995), Bonaparte (1996), Wilson and Smith (1996), Sereno (1997), Sereno (1998), Wilson and Sereno (1998), Bonaparte (1999), Wilson (2002), Upchurch et al. (2004), Harris and Dodson (2004), Salgado and Coria (2005), Gallina and Apesteguía (2005), Taylor and Naish (2005), Rauhut et al. (2005), Salgado et al. (2006), Remes (2006), Apesteguía (2007), Wilson et al. (2009), Suteethorn et al. (2010), Ksepka and Norell (2010), Whitlock (2011), Ibiricu et al. (2012), Mannion et al. (2012), Tschopp and Mateus (2013), Mocho et al. (2014) and Paulina-Carabajal and Calvo (2021).