Tengku Ahmad Rithauddeen bin Tengku Ismail (Jawi: تڠکو أحمد رضاءالدين بن تڠکو إسماعيل; 24 January 1928 – 29 April 2022) was a Malaysian politician and barrister who formerly served as chairman of the UMNO disciplinary board.

He was Kota Bharu Member of Parliament for five terms before losing his seat in the 1990 General Election to the Semangat 46 candidate.

He was also among few Malaysians awarded the Grand Cordon of the Order of the Rising Sun from Japanese Emperor, credited with strengthening Malaysian-Japanese relationship.

[1] He was also vocal in Malaysian politics, voicing several issues in regards to the post-BN social concerns.

[2] Tengku Ahmad Rithauddeen died on 29 April 2022 at his residence in Jalan Duta, aged 94.