However the law will not come into effect until December 1.
A Royal Assent ceremony took place yesterday, with the Welsh Assembly Minister for Environment, Energy and Rural Affairs Lesley Griffiths and First Minister Mark Drakeford present.
The legislation follows some 14 years of campaigning by the RSPCA, since the relevant powers were devolved to Wales - and will make it an offence to perform or exhibit a wild animal in a travelling circus.
Polling commissioned by the charity revealed that 74 per cent of people in Wales backed a ban on wild animals performing in circuses and 9,000 people had signed an RSPCA Cymru petition calling for the practice to be outlawed.
Claire Lawson, RSPCA assistant director for external relations in Wales, said: "While Royal Assent was something of a formality, it's another cause for celebration as a ban on the performance and exhibition of wild animals in circuses in Wales edges nearer.
"RSPCA Cymru has long campaigned on this issue - and this law makes such an important statement as to how society in Wales treats animals, and our norms and values towards our fellow living creatures.
"The strength of feeling in all corners of Wales is clear, and people across the country will join us in celebrating on December 1 when this out-dated activity is finally banned and consigned to the history books, once and for all."
Wales has now joined other nations in Great Britain by acting on this issue. In England, the Wild Animals in Circuses Act 2019 gained Royal Assent in July 2019, and came into force at the beginning of this year; while in Scotland, the Wild Animals in Travelling Circuses (Scotland) Act 2018 implemented a ban in May 2018.