Seventy police officers conducted 19 searches of premises seizing nine firearms, 36 grams of ice with a street value of $36,000 and 4.3 kilograms of cannabis worth more than $70,000.
Most items were seized in the state’s north-west.
Three alleged members of the Bandidos gang were searched at Devonport Airport.
Tasmania’s Assistant Police Commissioner Glenn Frame said this week’s raids had successfully dented the Bandidos’ presence in the state.
He admitted the introduction of another outlaw motorcycle gang in Tasmania could increase tension between the groups.
“That’s certainly something that could arise and we’re well aware of it and we’re taking action, including this week of action, to try to deter any unlawful activity between the gangs or that might involve innocent people,” he said.
He said there were about six outlaw motorbike gangs established in Tasmania but the Rebels posed the most significant threat.
Australian Federal Police Acting Manager of Organised Crime Anthony Hall said it is a problem nationwide.
“Outlaw motorcycle gangs are expanding their business model, using their techniques to exploit any crevice within Australian society to exploit the honest citizens of the country,” he said.