The users can now watch the channel as part of their £10 or £5 monthly Orange TV subscription.
The service will also feature video clips from National Geographic programmes including 'Amazing Moments' and 'Demolition Squad', which will be available for customers to download for the first time on mobile.
Deborah Tonroe, head of TV and video for Orange, said: "Orange TV has something for everyone. We offer a truly diverse selection of channels and programmes from factual documentaries to cartoons, live news to classic comedy."
National Geographic Channel is also available on the Vodafone and 3 mobile networks.
The deal adds to the channel's increasing digital strategy, which includes video-on-demand, interactive TV, podcasting and user-generated content.
The deal was brokered by Claire Woodward of digital media specialists Huge Entertainment, part of the Engine group.
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