Lord Sugar takes up his new role at YouView, the joint venture between the BBC, ITV, BT, Channel 4, TalkTalk, Arqiva and Channel 5, with immediate effect.
Meek joined what was then Project Canvas in July 2010, and subsequently oversaw the incorporation of YouView, the regulatory approval for the platform from Ofcom and the appointment of chief executive Richard Halton.
"Kip joined YouView at a pivotal time in our development and has helped us make a standards based, open internet-connected TV environment a reality," said Halton.
"We would like to thank him for his considerable contribution in the development of the next generation of television."
Meek added: "It has been apparent for some time that the YouView board would benefit from additional expertise in consumer marketing and technology delivery. Lord Sugar clearly supplies this. As the venture progresses towards launch, the change in chairman makes sense. I wish Lord Sugar well."
YouView will hope to draw on Lord Sugar's high profile in the media, but also his extensive experience in the consumer electronics industry.
After founding Amstrad in 1968, Lord Sugar built the company up to become the main supplier of set top boxes to Sky Digital, before selling the firm to Sky in 2007.
Discussing his appointment, TalkTalk chairman Charles Dunstone said: "Lord Sugar's experience in delivering set top box technology to the consumer is unrivalled and we are delighted that he will be with us as we introduce a new, enhanced television experience to homes across the UK.
"As we move from the development to the delivery stage I can't think of anyone better placed to help bring YouView to market than Lord Sugar."
Last week, Halton defended the decision to delay the launch of YouView until 2012, arguing that the new IPTV platform will be "worth the wait".