Moore, who left A&O in 1999 to join Norton Rose, was one of only two corporate partners in the firm's Singapore office.
Norton Rose Asia chief David Stannard said: "Chris leaving is a nuisance but we are looking to expand the corporate team in the region by at least one. That is likely to come through a lateral hire but possibly there will be internal growth."
The news of Moore's departure comes as Norton Rose itself lured back its former associate Stephen Begley from Lovells to join its partnership.
Begley, who has been of counsel at Lovells for more than two years ago, will be heading the firm's asset finance group in Hong Kong.
Begley takes on the position of asset finance head following partner Jeremy Gibb returning to the London office.
Stannard said it was great to be welcoming back "an old boy" who will be able to expand the asset finance team in Hong Kong, which is currently made up of associates and is run by partners from the Singapore office.
"Stephen started his practice in asset finance and forged links strongly in energy. This is where we see the asset finance practice moving and expanding into," said Stannard.