Shemshak () is a city in Rudbar-e Qasran District of Shemiranat County, Tehran province, Iran. A suburb of Tehran, Shemshak was established upon the merger of the former villages of Darband Sar, Darrud, Jirud, Sefidestan, Shemshak-e Bala, and Shemshak-e Pain in 2012.
At the time of the 2016 National Census, the population was 3,423 people in 1,197 households.