Numbers of adult scout leaders have also risen
The UK scout movement has seen its biggest rise in membership since 1972 - thanks largely to an increase in teenage volunteers from Wales.
In the last year 135 teenagers in Wales joined the scouts - up 7.6% on the previous year - taking the Welsh total to 15,395, the Scout Association said.
Five of the UK's top 10 fastest growing areas are in Wales, figures show, with Snowdonia/Anglesey in top spot.
"It's fantastic to witness such a huge surge," said Chief Scout Bear Grylls.
Brecknockshire came second in the Scout Association's list of top 10 growth areas, with Ceredigion fourth, Carmarthenshire sixth and Pembrokeshire eighth.
In all there were 647 new members in Wales last year, with numbers of adult members also rising for the second year running.
Their number grew from 2.2% in 2009 to 6.8% - more than double the UK average.
The Scout Association said its fifth consecutive year of expansion, which pushed total UK membership to 499,323, cemented its position as the largest co-educational youth movement in the country.
But despite the growth the association said overall waiting lists remained at an all-time high due to the need of more adult volunteers.
There are currently over 1,000 young people waiting to become scouts in Wales.
Mr Grylls said the rise in membership was proof that scouting is appealing more and more to teenagers.
"Scouting is empowering, wild and fun, and offers so many adventure-based activities for young people and adults alike," he said.
"My goal is for every young person that wants to be involved in Scouting to be able to be.
"So I hope to inspire even more adults to volunteer and help this happen."