Assembly Members have voted in favour of the motion for legalisation of cannabis for medicinal use.
AMs voted 31 to 18 in favour of lobbying the UK Government to act on decriminalisation of the drug.
But the vote is not binding on the Welsh Government.
Many people living with Multiple Sclerosis, Dystonia, Epilepsy and Cancer in Wales use illegally obtained cannabis for medical purposes. By doing so, they risk prosecution.
Leanne Wood AM, Mark Isherwood, Mike Hedges and Rhun Ap Iorwerth, tabled the motion.
There are growing number of countries which regulate the use of medicinal cannabis and it's derivatives, such as Canada, the Netherlands, and Israel.
Additionally, it has been legalised in more that 20 states in the United States.
The only cannabis based medication available in the UK is Sativex.
Wales became the first country in the UK to approve the prescription of it on the NHS in 2014.
It is for those suffering with MS in Wales.