Whitstable Lifeboat was launched at 3.20pm on Wednesday following a report of a person in the water possibly holding a dog off Leysdown, Isle of Sheppey.
The lifeboat arrived at the scene and along with the Sheppey Coastguard commenced a search of the area.
The lifeboat crew spoke to a swimmer and it was confirmed that he was not the person seen and was not involved.
The lifeboat continued the search but nothing was found and the lifeboat was released to return to station.
Crew: Helmsmen Dave Parry, Rob Judge and Ruth Oliver.
Launchers: : Andy Clarke (Tractor driver) and Andy Mayo.