LONDON, July 15 (Reuters) - SuperGroup (SGP.L), owner of the Superdry fashion brand worn by celebrities such as David Beckham and Zac Efron, beat forecasts as year profit more than quadrupled and said the 2010-11 year had started well.

"There is huge potential for this business both in the UK and internationally and, with a strong growth strategy, we are confident of achieving another successful year," Chief Executive Julian Dunkerton said on Thursday.

The retailer and wholesaler, whose shares have increased 60 percent since it floated in March, made an underlying pretax profit of 26.5 million pounds ($40.27 million) in the year to May 2.

That compares with analysts' consensus forecast of 25.9 million pounds, according to Thomson Reuters I/B/E/S, and 7.9 million pounds made in 2008-09.

The outcome was driven by its ongoing store roll-out and buoyant sales both in the UK and overseas.

SuperGroup, which trades from 45 stand-alone Superdry and Cult stores in the UK, 56 concessions in House of Fraser department stores and has a wholesale business in 36 countries, said sales jumped 83.1 percent to 139.4 million pounds.

Retail sales increased 75 percent to 85 million pounds, with sales at stores open over a year up 17 percent. Wholesale sales doubled to 54 million pounds.

The firm has a 20 stores a year opening programme and sees scope for 150 Superdry and Cult stores in Britain and Ireland. It is also targeting womenswear and the internet to drive growth.

Shares in SuperGroup, which listed at 500 pence, closed Wednesday at 800 pence, valuing the business at 633 million pounds.

(Reporting by James Davey, editing by Kate Holton)