Until the late 1970s, the military's primary mission was to prepare for an invasion of the Communist-controlled People's Republic of China (PRC) through efforts such as Project National Glory.

[44] The professional head of the Armed Forces is the Chief of the General Staff, who answers to the civilian command structure under the Minister of National Defense and the ROC President.

[59] Since the 2000s, the ROCN has tried to improve its asymmetric warfare capability to counter the much larger People's Liberation Army Navy by locally building smaller and stealthier craft, such as fast missile boats, corvettes, and submarines, though its destroyers and frigates remain the main component of the fleet.

[65] More recently, the main purpose of the Marine Corps has been to defend Taiwan by disrupting PRC amphibious operations and to serve as a rapid response force.

[69] In recent years the ROCAF had to send aircraft to respond to Chinese planes entering Taiwan's air defense identification zone.

[70] Founded on mainland China, the ROC Air Force on Taiwan received U.S. military assistance in the Cold War, including over 400 aircraft, which were mostly fighters.

[72] In the 1990s Taiwan began acquiring more modern aircraft to replace the F-5 and to counter the improving People's Liberation Army Air Force, including the F-16 Fighting Falcon and the Dassault Mirage 2000.

[68] Although the PLAAF has both technological and numerical superiority over the ROCAF, Taiwan has made efforts to improve its aircraft, including upgrading its F-16 fleet to the most advanced variant, the Block 70 Viper (F-16V).

[81] As of 2023, the Reserve was estimated to have a total of 1,657,000 reservists by the International Institute of Strategic Studies, including 1.5 million in the Army, 67,000 in the Navy, and 90,000 in the Air Force.

In 2012, ROC Ministry of National Defence announced that the length of service was reduced to 4 months from the original 1 year in December 2011 for those born after 1 January 1994, due to aims to establish an all-volunteer force.

[91] This policy was reversed in 2022, when president Tsai Ing-wen announced that conscription will revert back to 1 year from 2024, as relations with the PRC had deteriorated since at least 2016 when her party came into power.

[104] The White House had declined to sell 66 F-16C/D fighter planes as US Pacific Command has felt no need for advanced arms to be sold to the ROC.

[115] The primary goal of the ROC Armed Forces is to provide a credible deterrent against hostile action by establishing effective counterstrike and defense capabilities.

ROC military doctrine in 2004 centered upon the principle of "offshore engagement" where the primary goal of the armed forces in any conflict with the PRC would be to keep as much of the fighting away from Taiwan proper for as long as possible to minimize damage to infrastructure and civilian casualties.

Combating the enemy fleet and sinking transport ships would take out large amounts of the ground invasion force and permanently degrade amphibious capabilities.

The RoCAF is optimized for air superiority and was once the more formidable of the two countries, but current Chinese technology investments have made China much more able to contest airspace.

The RoCAF operates a nationwide air defense network to engage targets anywhere over the mainland; some anti-aircraft missile batteries are also located in underground silos.

[125] In 2019 Guatemalan Minister of Defense Major General Luis Miguel Ralda Moreno visited Taiwan and met with Taiwanese President Tsai Ing-wen.

[135] In 2007, a F-5F fighter operated by the Republic of China Air Force (ROCAF) crashed into base housing that was occupied by Singaporean personnel, killing the pilots.

[141] When the United States Congress enacted on September 30, 2002, the Foreign Relations Authorization Act for FY 2003, it required that Taiwan be "treated as though it were designated a major non-NATO ally.

[143] In recent years, the ROC military has again begun higher level cooperation with the United States Armed Forces after over two decades of relative isolation.

[145][146] In 2015 two United States Marine Corps F/A-18C Hornets made an unscheduled landing at Tainan Air Force Base after one of them developed an engine anomaly in-flight.

[148] Tsai said the weaponry would "greatly enhance our land and air capabilities, strengthen military morale and show to the world the US commitment to Taiwan's defense.

"[149] In May 2020, the U.S. Department of State approved a Foreign Military Sale of 18 MK-48 Mod 6 Advanced Technology Heavy Weight Torpedoes for Taiwan in a deal estimated to cost $180 million.

[123] In June 2020 the United States Army Special Forces published a promotional video which included footage of Green Berets training in Taiwan.

[153] In the 1960s West Germany participated in the Mingteh Project (Ming-teh-Gruppe in German) in which off-duty military officers were sent to Taiwan to advise the government of Chiang Kai-shek.

The parade consisted of indigenous missiles, U.S. Patriot II and Avenger anti-missiles systems, U.S.-made F-16s, French-made Mirages and Taiwan-made IDF fighters.

[162] After the International Atomic Energy Agency found evidence of the ROC's efforts to produce weapons-grade plutonium, Taipei agreed in September 1976 under U.S. pressure to dismantle its nuclear weapons program.

[166] In 1988 upon being questioned by Director of American Institute in Taiwan, David Dean in person with the United States satellite image recording a minimized nuclear test at Jioupeng military base field in Pingtung in 1986, Superior-general Hau Pei-tsun claimed that scientists in Taiwan had already produced the controlled nuclear reaction as the continuous progress in decades after the previous accomplishment equivalent to 1/6 of Hiroshima scale in South Africa in 1980, as per General Hau's Diary and President Nelson Mandela's later findings.

[172] During the 1995–1996 Taiwan Strait crisis, ROC President Lee Teng-hui proposed reactivating the program, but was forced to back down a few days later after drawing intense criticism from the U.S.