Citizens of the following countries can visit Taiwan for up to 30 days without a pre-approved visa:

Australia, Austria, Belgium, Brunei Darussalam, Canada, Costa Rica, Denmark, Finland, France, Germany, Greece, Ireland, Iceland, Italy, Japan, Republic of Korea, Liechtenstein, Luxembourg, Malaysia, Malta, Monaco, the Netherlands , New Zealand, Norway, Portugal, Singapore, Spain, Sweden, Switzerland, U.K. and U.S.A.

Visitors from all other countries should have a valid visa before departure.

More informations can be found at Bureau of Consular Affairs, Ministry of Foreign Affairs