The business tycoon took to Twitter.com on Wednesday (18Apr12) hoping to raise awareness of the crisis after he was touched by non-governmental organisation WildAid's campaign to end rhino hunting.
Rhino horns are in high demand in China and Vietnam, where many residents believe they have medicinal properties.
In his tweet, Branson writes, ""One rhino is killed illegally every 20 hours in South Africa. Act now to savetherhino.""
The Virgin empire magnate also posted a blog entry on his official website in a bid to encourage fans to donate towards WildAid's efforts.
He writes, ""Disturbed to see continuing crisis in poaching of rhinos... Incredibly, 448 rhinos were illegally killed in South Africa in 2011 - that's one killed every 20 hours. With fewer than 5,000 black rhinos left in the world, at this rate every rhino will be gone within ten years... Act now to save the rhinos.""