The Székely Land (pronounced [ˈseːkɛj]; Hungarian: Székelyföld; Romanian: Ţinutul Secuiesc; German: Szeklerland; Latin: Terra Siculorum) or Szekler Land refers to the territories inhabited mainly by the Székely, a Hungarian-speaking ethnic group from eastern Transylvania. They live in the valleys and hills of the Eastern Carpathian Mountains, corresponding to the present-day Harghita, Covasna, and parts of Mureş Counties in Romania.

Originally, the name Székely Land denoted an autonomous region within Transylvania. It existed as a legal entity from medieval times until the Austro-Hungarian Compromise of 1867, when the Székely and Saxon seats were dissolved and replaced by the county system. Along with Transylvania, it became a part of Romania in 1920, returned to Hungary in 1940 and was again attached to Romania in 1945. The area was a Hungarian autonomous region within Romania between 1952 and 1968, and today there are Székely autonomy initiatives to reach a higher level of self-governance for this region within Romania.