The coastguard received a mayday call alerting them to the incident shortly before 6pm on Monday.
Lifeboats from Buckie, MacDuff and Fraserburgh have been launched to assist the Banff coastguard rescue team, while the coastguard search and rescue helicopter from Inverness is also combing the area.
Three local fishing boats have also responded to a call to join the search.
A spokesperson for the Maritime and Coastguard Agency said: “At around 5.50pm today, HM Coastguard received a mayday call on channel 16 from a vessel with three persons onboard reporting that they were abandoning ship in the Moray Firth area.
“Banff Coastguard Rescue Team, Buckie, MacDuff and Fraserburgh Lifeboats and HM Coastguard SAR helicopter from Inverness are currently searching the area.
“HM Coastguard has issued a mayday relay broadcast to all vessels in the area asking them if they can assist in the search.
“Three local fishing vessels have responded to the relay broadcast and have also joined the search.”