As widely anticipated, the full Sky News HD service will launch on election night, May 6, on Sky channel 517.
Meanwhile Sky has just announced nine-month profits to March of £707m, more than twice the £339m of the same period last year, and 428,000 new HD subscribers signed-up.
BSkyB chief exec Jeremy Darroch says "We have seen a huge response to our decision to cut the upfront cost of HD," adding that "our financial performance is accelerating".
BSkyB has confirmed that Sky News is now previewing in high definition on channel 517. The TV debate between the three main party leaders on April 22nd will be broadcast in HD too, says Sky.
Sky News will launch in high definition from spring 2010. The move will follow an upgrade to studios, production facilities and news gathering operations at Sky's facilities in the UK and overseas.
The high-definition service will be simulcast alongside Sky News' existing standard-definition channel.
The commitment to launch in HD follows the channel's successful HD broadcast, and online streaming in HD, of President Obama's Inauguration in January.
Jeremy Darroch, Sky's Chief Executive, says: "Sky News continues to break new ground in television news and it's only natural for it to become the first UK news channel to launch in HD."
Sky News' production teams will be given special training to get the most from HD technology, alongside staff in areas such as make-up, which requires special techniques to be used for HD broadcasts.