2008 ROC vice presidential election In May 2007, Siew was mentioned as a possible running mate for KMT presidential nominee
Ma Ying-Jeou. This speculation came to fruition after Legislative Yuan Speaker
Wang Jin-pyng declined Ma's offer to be his running mate. On 23 June 2007, ending weeks of speculation, Ma formally introduced Siew to be his vice-presidential running mate. The 2008 run is Siew's second ticket, having been selected also as the vice-presidential candidate of Lien Chan's KMT ticket in 2000. On March 22, Ma and Siew won the 2008 presidential elections. He and Ma won with 7,659,014 (58.45%) votes against
Hsieh and
Su's 5,444,949 (41.55%) votes.
2008 Boao Forum for Asia On 11 April 2008, Vincent Siew departed
Taiwan to attend the
Boao Forum for Asia, held in
Boao,
Hainan, which is administered by mainland China. Siew is a founding delegate of the forum from 2001, and he attended once again in his capacity as chairman of the Cross-Straits Common Market Foundation. Siew had met with
Chinese Communist Party general secretary Hu Jintao in Bo'ao in 2001. However, his special status as the vice president-elect in 2008 made his attendance more significant, but also more controversial in Taiwan. His meeting with Hu Jintao was the highest level exchange between Taiwan and mainland China since the
2005 Pan-Blue visits to mainland China. The level of reception for Siew in Hainan was scaled accordingly and was equivalent to that reserved for Lien Chan in 2005. On 12 April 2008, Vincent Siew met with Hu Jintao at the Boao Asia Forum as part of the Cross-Strait Common Market Foundation delegation, which also included other former and future government officials and business leaders from Taiwan. At the meeting, Siew and Hu exchanged their optimism for cross-strait relations under the new Taiwanese leadership of
Ma Ying-jeou and Vincent Siew. Hu asked Siew to convey his greetings to Ma Ying-jeou, Kuomintang chairman
Wu Po-hsiung and chairman emeritus Lien Chan. Siew raised the issue of regular cross-strait flights and the resumption of regular talks between the two governments, propositions to which Hu expressed agreement.
Vice presidency sworn-in Siew, along with Ma, was sworn in on 20 May 2008 in Taipei to be
Vice President and President of the Republic of China respectively.
First overseas trip as vice president On 4 September 2008, Siew embarked on his first overseas trip as vice president, visiting
Swaziland for four days. Siew's trip aimed to cement further the diplomatic ties between the two countries, and to celebrate
King Mswati III's fortieth birthday. Foreign Minister
Francisco Ou accompanied Siew on the trip.
2012 vice presidency election Siew declined to run for a second term in Ma's 2012 re-election bid. Ma, instead, nominated Premier
Wu Den-yih for the vice presidential slot on the ticket. ==Post political career==