The Rural Crime Prevention Team are investigating the alleged theft of 350 ewes from a property at Collinguillie.
Police say the Dorper mixed-aged ewes are believed to have been stolen from a property on Mundowey Lane sometime between 20 and 25 March.
Police say investigators from the Rural Crime Prevention Team from Cootamundra have commenced an investigation.
As inquiries continue, police urge anyone with information to call Cootamundra Police Station on 02 6942 0099 or contact Crime Stoppers on 1800 333 000 or at Crime Stoppers. Information is treated in strict confidence.
The public is reminded not to report information via NSW Police social media pages.