The Timorese Democratic Union (Portuguese: União Democrática Timorense, UDT) is a conservative political party in East Timor.

The founders of the party included the brothers Mário, Manuel and João Carrascalão, Domingos de Oliveira (the first General Secretary), Francisco Lopes da Cruz and César Augusto Mousinho (then Mayor of Dili and Vice President of the UDT).

[2] This alliance lasted for only five months and broke up among accusations that Fretilin was not exercising control over its more extreme members, specifically those of Communist leanings.

Although by this time UDT leaders like Francisco Lopes da Cruz had held meetings with BAKIN, the then Indonesian military intelligence, which had signalled Jakarta's misgivings about an independent state under Fretilin control.

On August 11 of that year, after a majority in favour of Fretilin threatened to emerge, the UDT staged a coup against the Portuguese administration, and a three-month civil war erupted.

One of the UDT's most senior leaders, Mário Viegas Carrascalão, sided with the Indonesian regime and served as the governor of Indonesia's 'Timor Timur province' between 1987 and 1992.

[6] After Domingos de Oliveira, Cipriano J. da Costa Gonsalves,[7] and then Francisco David Xavier Carlos were Secretary General.

After the end of the occupation, João Viegas Carrascalão was Minister for Infrastructure during the UN administration and coordinated the start of the reconstruction of East Timor.

In July 2007, the UDT merged with five other parties that had also failed to reach the three per cent threshold in the parliamentary elections to form the Liga Democrática Progressiva (LDP).

[11] For the presidential elections in East Timor in 2012, UDT President Santos declared in 2011 that he wanted to support the former military commander-in-chief Taur Matan Ruak in his candidacy, even though he emphasised his independence from all parties.

[16] Following the political unrest between Fretilin and AMP (Aliança Maioria Parlamentar), comprised by CNRT, PLP and KHUNTO, the President of Timor-Leste decided to make another parliamentary snap election to solve the problem.

[26][27][28] The UDT wanted to run in the 2023 parliamentary elections in East Timor as part of the Frente Ampla Democrática (FAM) electoral alliance.

[29] However, on 14 March, the PDN withdrew from the alliance and submitted its own list of candidates to the Supreme Court of East Timor (Tribunal de Recurso).