Thiri Maha Thu Dhammayaza (Burmese: သီရိမဟာသုဓမ္မရာဇာ, Pali: Sīrimahāsudhammarājā; born Myo Tu; 1847 – 1879), commonly known as the Prince of Mekkhaya, was a first-ranked royal prince of the late Konbaung dynasty. He was a senior son of King Mindon and was the Governor-general of Taungdwingyi Province. He was considered one of the four most skilled sons of King Mindon, alongside the princes of Thonze, and Myingun. He was called 'the second Prince of Mekkhaya' by historians, not to be confused with the first Prince of Mekkhaya who compiled the first English–Myanmar dictionary.