The latest (June 2019) vector data sets include "national and provincial road centerline" had updated and open to the public.

This update is produced from the latest Taiwan e-Map of National Land Surveying and Mapping Center, including 15 vector data sets. For more details about the aforementioned ones, please refer to the attachment and available for access to the following websites:
(1) Taiwan Map Store(https://whgis.nlsc.gov.tw)
(2) TGOS(https://www.tgos.tw)
(3) MOI Open Data(https://data.moi.gov.tw)
(4) DATA.GOV.TW(https://data.gov.tw)