Alagiah Thurairajah (Tamil: அழகையா துரைராசா, romanized: Aḻakaiyā Turairācā; 10 November 1934 – 11 June 1994) was a Sri Lankan academic and vice-chancellor of the University of Jaffna.

[1][2] After completing school he commenced studies at the University of Ceylon in July 1953, graduating with a BSc degree in civil engineering in 1957.

[1][2] This research earned Thurairajah a PhD in June 1962 with a thesis titled Some shear properties of kaolin and of sand.

[1][2] His younger son, Alahesh Thurairajah continued the Legacy of his father and earned a great reputation in geotechnical community.

[1][2] He was posthumously awarded the Maamanithar (Great Man) honour by the LTTE Liberation Tigers of Tamil Eelam.