The Toshkan (or Toxkan, Kyrgyz: Какшал - Kakshal) is a river in the Tien Shan mountains in the border area between China and Kyrgyzstan. The Toshkan has its sources in the mountains south of the Kyrgyzstani city of Naryn. It then flows towards the east and into the Xinjiang province of China. It continues east, running parallel to the Tien Shan mountains, until its confluence with the Aksu River near the city Aksu. The Toshkan is the main tributary of the Aksu.