The person was rescued by Coastguard at about 6am.
Council harbourmasters from both Coromandel and Whitianga attended to the scene amid concerns that an estimated 250 litres of fuel on board was leaking into the water.
They declared a tier 2 marine oil spill response, meaning the leak was small and impact to the environment would be minimal.
"The good news is that with a relatively small amount of diesel like this on the surface, it's likely there will be little or no effect on the environment from this incident," said regional on-scene commander, the council's Richard Barnett.
He said the harbourmasters were working to collect from the water as much of the floating debris from the yacht as possible.
The yacht, which is still stuck on the rocks, was expected to be salavaged by Tuesday morning.
People needing more information can contact the Waikato Regional Council on 0800 800 401.