Provincial Highway 1 (Chinese: 台1線; pinyin: Tái Yī Xiàn) is a 461.081 km (286.502 mi)-long[1] Taiwanese provincial highway that starts in the north of the country near Taipei Main Station and ends in the south at Fangshan, Pingtung County.

PH 1 continues through Miaoli County, connecting the coastal townships of Zhunan, Toufen, Zaoqiao, Houlong, Xihu, Tongxiao, and Yuanli before entering Taichung City.

The highway briefly runs concurrent with PH61 (Xibin Expressway, 西濱快速道路) in Tongxiao, Miaoli.

The highway passes through the districts of Dajia, Qingshui, Wuqi, Longjing, and Dadu, before exiting the city in Wuri.

From Yuanlin the highway continues through a number of rural townships, including Puxin, Yongjing, Tianwei, Beidou, Xizhou, and Pitou.

The highway enters Xiluo in Yunlin County via Xizhou Bridge (溪州大橋), passing through Zhuoshui River.

The urban and rural districts served by PH 1 include Houbi, Xinying, Liouying, Lioujia, Guantian, Shanhua, Xinshi, and Yongkang.