Juli Soler, a restaurateur who put Ferran Adrià in charge of the kitchen at El Bulli in Catalonia, Spain, and helped him transform the restaurant into one of the most innovative centers of gastronomy in the world, died on Monday at his home in Rubí, near Barcelona. He was 66.

Mr. Adrià announced the death in a post on Twitter on Monday. The cause, reported in the Spanish press, was degenerative nerve disease.

Mr. Soler became manager of Hacienda El Bulli, as it was then known, in the early 1980s, when it was one of Spain’s few Michelin-starred restaurants. He removed the “Hacienda,” which he hated, and hired a talented, modern-minded young French chef, Jean-Paul Vinay, who added a second star to the restaurant in just two years.

When Mr. Vinay left to start his own restaurant in 1984, Mr. Soler began looking closely at a young chef he had hired as a line cook, whose ferocious work ethic and creative streak intrigued him.