He moved to Ireland after graduating from the Croydon School of Art, London. Known for his hand-crafting, beading and appliquée to garments, Rocha first established a name for himself with his Chinatown label in Dublin in the 1980s and later designing clothing for both men and women in the Irish high street stores A Wear and their luxury stores Brown Thomas. Rocha designed a range of cut crystal stemware and vases for Waterford Crystal in collaboration with glass designer Marcus Notley, until that firm"s closure in 2008.
The brand relaunched in 2010 and Rocha"s crystal product ranges became available again.
By 1993, he was named Designer of the Year at the British Fashion Awards. Rocha runs his own "John Rocha", "John Rocha Jeans", "Rocha John Rocha" and "John Rocha Jewellery" labels alongside a diffusion clothing, homewear and accessories label for the department store Debenhams.
Rocha has also designed the interiors of the Morrison Hotel in Dublin and the Orion Building in Birmingham. Rocha continues to produce a "pret-a-porter" womenswear and menswear range which he showcases twice annually at the British Fashion Council sponsored London Fashion Week (February & September).
His John Rocha lifestyle boutique opened on Dover Street, London, in 2006.
His design business, operating as Three Moon Design, is located at Dublin"s Ely Place with a turnover of €200 million per year
Rocha was made a Commander of the Order of the British Empire (Commander of the Order of the British Empire) in 2002 for his contributions to the British fashion industry. In 2014 Rocha showcased yet another successful Spring/Summer collection at London Fashion Week. In 2010 Rocha was one of six contemporary, internationally renowned Irish fashion designers featured on a set of Irish postage stamps issued by An Post.
The other designers featured were Paul Costelloe, Louise Kennedy, Lainey Keogh, Philip Treacy and Orla Kiely.