SK Telecom Co., Ltd. (Hangul: SK텔레콤 or 에스케이텔레콤) is a South Korean wireless telecommunications operator, it is part of the SK Group, one of the country's largest chaebols.

SK Telecom is South Korea's largest wireless carrier, it leads the local market with 50.5 percent share as of 2008. Since its creation in 1984, the company has evolved from a first generation analog cellular system, to second generation CDMA, then to the world's first third-generation synchronized IMT-2000 cellular system. SK Telecom also became the world’s first carrier to commercialize HSDPA in May 2006. SK expanded into the landline market by acquiring second-rated fixed-line operator Hanaro Telecom in February 2008.

The company’s online brands include "Nate," a web portal; "June," a mobile multimedia service; "Moneta," an e-banking mobile app; "Nate Drive," a telematics service and "Digital Home," an online interface to remote-control household appliances.

Online services are offered through tech subsidiary SK Communications, which also dominates the social networks market in South Korea. "Cyworld" is the largest social media site by membership and "NateOn" is the number one instant messaging client.