The Ljubljanica Sluice Gate (Slovene: Zapornica na Ljubljanici), or the Partition (Pregrada),[1]: 180–181  is a sluice gate and a triumphal arch on the Ljubljanica River in Ljubljana, the capital of Slovenia.

[2] It is located between Cukrarna (a former sugar factory) and Vraz Square (Vrazov trg) in the Center District, east of the Ljubljana old town, a bit downstream of Ambrož Square (Ambrožev trg).

[3] It was designed in 1939 by the Slovene architect Jože Plečnik, who envisaged it as a monumental farewell to the Ljubljanica River on its exit from the Ljubljana city centre.

[5] Since July 2009, it has been protected as a monument of national significance, along with other major works by Plečnik.

[6] Since August 2021, the Ljubljanica Sluice Gate has been inscribed as part of Plečnik's legacy on the UNESCO World Heritage List.