Martyrs' Day (Burmese: အာဇာနည်နေ့, pronounced [ʔàzànì nḛ]) is a Burmese national holiday observed on 19 July to commemorate Gen. Aung San and six other leaders of the pre-independence interim government—Thakin Mya, Ba Cho, Abdul Razak, Ba Win, Mahn Ba Khaing and Sao San Tun—all of whom were assassinated on that day in 1947. It is customary for high-ranking government officials to visit the Martyrs' Mausoleum in Yangon in the morning of that day to pay respects.

On July 19, 1947, at approximately 10:37 a.m., BST, several of Burma's independence leaders were gunned down by a group of armed men in uniform while they were holding a cabinet meeting at the Secretariat in downtown Yangon. The assassinations were planned by a rival political group, and the leader and alleged master-mind of that group Galon U Saw, together with the perpetrators, were tried and convicted by a special tribunal presided by Kyaw Myint with two other Barristers-at-law, Aung Thar Gyaw and Si Bu. In a judgment given on 30 December 1947 the tribunal sentenced U Saw and a few others to death and the rest were given prison sentences. Appeals to the High Court of Burma by U Saw and his accomplices were rejected on 8 March 1948. In a judgment written by Supreme Court Justice E Maung (1898–1977) on 27 April 1948 the Supreme Court refused leave to appeal against the original judgment. (All the judgments of the tribunal, the High Court and the Supreme Court were written in English. The judgment of the tribunal can be read in "A Trial in Burma" by Dr Maung Maung (Martinus Njhoff, 1963) and the judgment of the High Court and Supreme Court can be read in the 1948 Burma Law Reports.)