This is a list of rivers in Taiwan that are 19 kilometers or longer:

Lanyang River - Yilan County - 73 km
Yilan River - Yilan County - 25 km
Tungshan River - Yilan County - 24 km
Chingshui River - Yilan County - 25 km
Lotsao River - Yilan County - 21 km

Shuang River - Taipei County - 27 km

Danshui River - Taipei County, Taoyuan County, Taipei City, Hsinchu County - 159 km
Keelung River - Taipei County, Taipei City, Keelung City - 89.4 km
Xindian River - Taipei County, Taipei City - 82 km
Jingmei River - Taipei County, Taipei City - 28.1 km
Peishih River - Taipei County, Yilan County - 50 km
Nanshih River - Taipei County - 45 km
Tahan River(Takekan River) - Taipei County, Taoyuan County, Hsinchu County - 135 km
Sanhsia River - Taipei County - 22.6 km

Nankan River - Taoyuan County - 31 km

Fengshan River - Hsinchu County - 45 km

Touchien River - Hsinchu County - 63 km

Houlung River - Miaoli County - 58 km

Ta-an River - Miaoli County, Taichung County - 96 km

Tachia River - Taichung County - 124 km

Tatu River (Wu River) - Taichung County, Changhua County、Nantou County - 116 km
Maolo River - Taichung County, Changhua County, Nantou County - 32 km
Nankang River - Taichung County - 35 km

Choshui River - Nantou County, Changhua County, Yunlin County - 186 km
Chingshui River - Taichung County, Chiayi County, Tainan County - 51 km
Shuili River - Taichung County - 19 km
Wanta River - Taichung County - 37 km
Kashe River - Taichung County - 48 km

Peikang River - Yunlin County、Chiayi County - 82 km
Tahukou River - Tainan County - 33 km
Santieh River - Tainan County - 35 km

Putzu River - Chiayi County - 75 km

Pachang River - Chiayi County, Tainan County - 81 km
Touchien River - Tainan County - 28 km

Chishui River - Tainan County - 65 km
Kuichung River - Tainan County - 35 km
Paishui River - Tainan County - 20 km

Tsengwen River - Chiayi County, Tainan County, Tainan City -130 km

Lanshui River - Tainan County, Tainan City - 41 km

Erhjen River - Tainan County, Tainan City, Kaohsiung County - 65 km

Akungtien River - Kaohsiung County - 38 km
Fengshan River- Kaohsiung County - 20 km
Tienpao River- Kaohsiung County, Kaohsiung City - 32 km

Kaoping River - Kaohsiung County, Pingtung County - 171 km
Chishan River - Kaohsiung County, Pingtung County - 30 km
Ailiao River - Kaohsiung County, Pingtung County - 76 km
Wulo River - Pingtung County - 48 km
Fantzuliao River - Pingtung County - 26 km
Chokou River - Kaohsiung County - 59 km
Laonung River - Kaohsiung County - 100 km
Kumai River - Kaohsiung County - 48 km

Tungkang River - Pingtung County - 47 km

Linpian River - Pingtung County - 42 km

Peinan River - Taitung County - 84 km

Shiukuluan River - Hualien County - 81 km
Fuyuan River - Hualien County - 28 km
Fengping River - Hualien County - 37 km
Lekuleku River - Hualien County - 54 km

Hualien River - Hualien County - 57 km
Mukua River - Hualien County - 42 km
Shoufeng River - Hualien County - 37 km
Wanli River - Hualien County - 53 km

Other websites 
Rivers of Taiwan(台灣河川) (traditional Chinese)
Water Resources Agency, Ministry of Economic Affairs - Let's look at rivers (經濟部水利署-讓我們看河去) (traditional Chinese)
Rivers of Taiwan 
The Hydrology of Taiwan 

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