The attack happened at the hall on the Duneaney Road area of Glarryford, Ballymena, on Monday night.
Sergeant Patton said: “At around 7:45pm, the remains of a suspected petrol bomb were found outside the premises.
“Minor damage was caused to the front door of the property as a result of the incident.
“Enquiries are continuing but the incident is being treated as a hate crime.
“We are appealing to anyone with any information in relation to this incident to contact police on 101 quoting reference number 178 18/9/18.
“Alternatively, information can also be provided to the independent charity Crimestoppers on 0800 555 111 which is 100% anonymous and gives the people the power to speak up and stop crime.”