More than 74 festival goers smuggled drugs into the Dragon Dreaming Music Festival at Wee Jasper over the weekend.
Cannabis, ecstasy, heroin, ice and magic mushrooms were among drugs seized at the music and arts festival held near Yass.
Two people were arrested for drug supply and numerous others for drug possession.
Hume and Monaro Local Area Command police officers conducted a four-day high visibility operation between Friday, October 24 and Monday, October 27 to target anti-social behaviour and boost safety.
A team of 18 police and two drug detection dogs monitored about 2500 festival goers over four days.
Police also targeted drug-driving among drivers leaving the festival on the Sunday.
Twelve motorists underwent random drug tests. Two people were arrested after allegedly testing positive to prohibited drugs. Their samples have been sent for further analysis.
Inspector Evan Quarmby said police were disappointed to see so many people caught with prohibited drugs.
"Police were kept busy during the festival with 17 people found with prohibited drugs in the first two hours of the operation," he said.
"To end up with 74 drug detections is a major concern and police will work closely with festival organisers to ensure future events are safe for everyone attending.
"The efforts of police in detecting these drugs are highly commendable but we need people attending these events to think about the dangers and conduct themselves responsibly and within the law."