WA Police said the 29-year-old woman had been charged with possessing methylamphetamine with intent to sell or supply, possessing a smoking implement and wilfully destroying evidence.
She and a 31-year-old Marangaroo man were charged by meth enforcement taskforce officers after they seized drugs and a firearm on Thursday, October 4.
Police said they will allege that officers stopped a vehicle containing two occupants as it left an address in Marangaroo.
A search of the vehicle located a quantity of methylamphetamine and ammunition.
A warrant was then executed at the address in Marangaroo, where police allegedly located a hidden semi-automatic pistol.
The Marangaroo man, who is member of the Rebels OMCG, has been charged with aggravated possession of an unlicensed firearm.
He was due in the Perth Magistrates Court on Friday, October 5.