Leul Ras Kassa Hailu KS, GCVO, GBE, (Amharic: ?? ??? ???; 7 August 1881 – 16 November 1956) was a Shewan nobleman, the son of Dejazmach Haile Wolde Kiros of Lasta, the ruling heir of Lasta's throne and younger brother of Emperor Tekle Giyorgis II on his mother's side, and Tisseme Darge, the daughter of Ras Darge Sahle Selassie, brother of Menelik II's father.
John Spencer, who advised Ras Kassa during the writing of the 1955 Constitution of Ethiopia, described him as "surely the most conservative of all the rases in constant attendance at the court." Spencer continued his description of the aristocrat by noting that he rarely saw the Ras "in other than Ethiopian national dress.
Large, bearded and silent, this imposing dignitary wore a black cloak with gold clasps worked into the form of lion heads.
In working sessions, he used to take out with considerable pride a pair of folding half-lens spectacles with gold frames and bows."