Four kayaks were stolen from Ulley Country Park in an early morning raid.
They were taken at 2am on Monday, with the offenders caught on CCTV.
A South Yorkshire Police spokesman said: "Four kayaks were stolen from Ulley activity centre, based in Ulley Country Park.
"The offenders have been caught on CCTV and officers will be making enquiries to trace the offenders, but we need to know where these Kayaks are so that they can be returned to their owner.
"Do you know anything about this crime?"
Call South Yorkshire Police on 101.