The Daily Telegraph reports:
His lung was pierced by one of the animal's horns as he took part in the annual run. Nine others were injured in a dangerous race that saw one bull break away from the pack and charge sprinters.
The man, whose nationality and age have not yet been released, was gored in the neck and lung as he ran the half mile course through the cobbled streets of the northern Spanish town.
He is dead. He had been hit by a horn that punctured a lung," a spokesman for organisers of the annual San Fermin festival confirmed.
Television footage showed that the bull, a brown beast named Cappucino, broke away from the pack of five others and six steers which carried on running the course without him. Once separated the bull became disorientated and aggressive and began charging at the crowds of runners.
One man was flipped into the air and then lay curled on the ground as the bull repeatedly charged him. Others attempted to leap over the wooden barrier to escape his horns.
At least three other people were being treated for injuries inflicted by the bull's horns and another six suffered minor injuries, said a spokesman at the Virgen del Camino hospital in Pamplona.
Friday's run, the fourth of eight held during San Fermin, was by far the most perilous of this year's festival and raised the death toll to 15 since record-keeping began in 1911.
The last fatality occurred in 2003, when local man Fermin Etxberri, 63, was trampled to death. Friday's death was the first fatal goring since that of American Matthew Tassio in 1995.
Tens of thousands travel to Pamplona each July to participate in the fiesta made famous by Ernest Hemingway in his novel, The Sun Also Rises.
Sporting white clothes and red neckerchiefs thrill seekers stay up all night drinking at what has become one of Europe's biggest street parties before testing their bravado in the morning runs.