Emergency services were alerted when six people were caught in a rip at Mokau beach on Saturday afternoon.
The alarm was raised at 1.30pm.
The scene was attended by police, an ambulance and the Taranaki Community Rescue Helicopter.
A rescue helicopter spokesman said four of the swimmers had held on to a kayak and with the help of a second kayaker, were assisted back to shore.
The helicopter took a 9-year-old boy to Taranaki Base Hospital in a stable condition.
- Taranaki Daily News
What's your expectation of former tropical cyclone Pam?Related story: Cyclone Pam hits New Zealand
Get Taranaki's frequent news and sport updates
Get your mid week news fix
Get your South Taranaki news online