Muhammed Ali Khan Wallajah (1717–13 October 1795) is the Nawab of Arcot in India and an ally of the British East India Company.

Muhammed Ali Khan Wallajah was born to Anwaruddin Muhammed Khan, by his second wife, Fakhr un-nisa Begum Sahiba, a niece of Sayyid Ali Khan Safavi ul-Mosawi of Persia, sometime Naib suba of Trichonopoly, on July 7, 1723 at Delhi.

Muhammed Ali Khan Wallajah, the Nawab of Arcot, often refers to himself as the Subedar of the Carnatic in his letters and correspondence with the Mughal Emperor Shah Alam II.