Yunlin County is located in the northern part of the Chiaan Plain. It is about 38 kilometers from north to south and 50 kilometers from east to west. The total area is 1,290.84 square kilometers, divided into 20 districts with a population of 753,254. Nantou County lies to the east border and the Taiwan Strait lies to the west. The northern border lies to Chang Hua County which is separated by the Choshui River and Chiayi County lies across the Beigang River from the Southern border. 

　Administrative divisions of Yunlin County included the below townships:
　Mailiao Township, Lunbei Township, Erlun Township, Xiluo Township, Citong Township, Linnei Township, Taixi Township, Dongshih Township, Baojhong Township, Yuanchang Township, Tuku Township, Dapi Township, Huwei Township, Douliu City, Dounan Township, Gukeng Township, Sihhu Township, Kouhu Township, Shueilin Township, Beigang Township.