The substances decriminalised include heroin,cocaine and speed.
Health Minister Rachel Stephen-Smith said focusing on harm-minimisation rather than punishing drug users was the way forward.
“The ACT has led the nation with a progressive approach to reducing the harm caused by illicit drugs with a focus on diversion,access to treatment and rehabilitation and reducing the stigma attached to drug use,” she said.
“This sensible reform is based on the expert advice that a health focused,harm reduction approach delivers the best outcome for people using drugs.”
There will be a 12-month transition period,meaning the laws won’t kick in until October 2023.
The government said it would use the transition period to bolster oversight arrangements and train frontline workers including police.