《忧郁的星期天》（英语：Gloomy Sunday，匈牙利语：Szomorú Vasárnap），也译作《黑色的星期天》，是匈牙利自学成才的作曲家莱索·塞莱什（Rezső Seress，1899－1968年）谱写于1933年的一支歌曲。歌曲原名为《Vége a Világnak (世界末日)》，以乐谱的形式发行，随后歌词改用诗人 László Jávor 的版本，歌曲则于1935年在匈牙利以 《Szomorú Vasárnap (忧郁的星期天)》的名称录制发行。
这首歌于1936年同时被Sam M. Lewis以及Desmond Carter改编成英文，也在英语世界造成话题，最后，由比莉·荷莉戴于1941年所翻唱Lewis的版本最为出名。

"Gloomy Sunday", also known as the "Hungarian Suicide Song", is a song composed by Hungarian pianist and composer Rezső Seress and published in 1933.

The original lyrics were titled Vége a világnak (The world is ending) and were about despair caused by war, ending in a quiet prayer about people's sins. Poet László Jávor wrote his own lyrics to the song, titled Szomorú vasárnap (Sad Sunday), in which the protagonist wants to commit suicide following his lover's death. The latter lyrics ended up becoming more popular while the former were essentially forgotten. The song was first recorded in Hungarian by Pál Kalmár in 1935.