Vietnam passport holders are not eligible for visa-free entry and are required to get a Tourist Visa or Travel Authorization Certificate prior to arrival in Taiwan. Taiwan Tourist visas are valid from 30 to 180 days upon request. You can apply at the Taiwanese Embassy or Consulate in your current country.
The adjustments come following the consultations between the Ministry of Foreign Affairs, the National Immigration Agency, and the Tourism Bureau which aims to further the interactions with the 10 members of the Association of Southeast Asian Nations. Currently, nationals of Philippines, Brunei, Malaysia, Singapore, and Thailand enjoy visa-free entry to Taiwan.
For Vietnamese however, can get a Travel Authorization Certificate online who hold permanent resident certificates issued by Australia, Canada, Japan, Korea, New Zealand, Schengen Agreement signatories, the United Kingdom, or the United States, or hold a visa or a resident card from one of these countries either is valid or expired within 10 years from the date of expected arrival in Taiwan.
Vietnam citizens who are not eligible for the said certificate may apply for regular tourist visas at Taiwan’s consulate and embassy in Hanoi and Ho Chi Minh City.
Possible Lift of Visa for Vietnamese
Taiwan announced its New Southbound Policy, to build a closer people-to-people exchange of visits and an economic community between Taiwan and Vietnam. This is a good hint that Vietnam and Taiwan will lift their visa policies to both of its citizens and travel freely without spending time and money to get visas.
As of now, there are no updates from the Taiwanese and Vietnamese governments about their initiatives in lifting visas.