The death comes as new leftist mayors who swept to power across the country following May local elections mull eliminating funding for bull festivals, which see crowds of people run ahead of herds of bulls, while other towns boost their security measures.
The unidentified man in his late 40s was struck by a bull several times during a run in the northeastern town of Borriol on Saturday and died in hospital, a local police spokesman said.
Festivities were cancelled in the town of some 5,000 residents following the death.
This year's toll matches the record of ten deaths in bull runs set in 2009.
Last weekend alone four men died after being gored by half-tonne fighting bulls in four different towns.
One of the victims, a 55-year-old man, was caught on video being repeatedly gored by a bull as he lay on the ground in front of protective barrier that separate onlookers from bull run participants.
"It is an inevitability, an accumulation of coincidences, due mainly to the hordes of people who go see the bulls," said Alberto de Jesus, director of bullfighting magazine "Bous al Carrer".
More bull runs
Nearly 16,000 town festivals will include bull events this year, nearly 2,000 more than last year, according to culture ministry figures.
"Town halls always have more bull runs the year of municipal elections, the number of fiestas shoots up because they are popular," said Vicente Ruiz, the editor of El Mundo newspaper and a regular contributor to bullfighting blog La Cuadrilla.
Most bull runs are held in August and September when towns hold festivals in honour of patron saints.
Ten people were gored this year during Spain's most famous bull running festival, the week-long San Fermin fiesta in July.
Some towns have responded by boosting safety measures.
The town of Perales de Tajuna, some 40 kilometres (25 miles) southwest of Madrid, plans to have five ambulances on standby for its annual bull run on August 30, instead of just two as required by local regulations.
"First there are fireworks, then a procession in honour of the Virgin, finally the bulls. The fiesta is what gives the town its identity," the mayor of the town, Yolanda Cuenca Redondo, said.
'Not a game'
Jorge Rosco, a 37-year-old gas distributor who takes part in 25-30 bull runs across Spain each year, said the problem is that bull runs had become too crowded with many reckless participants.
"It is not possible to have more security measures than there are now. But there are many more people, so many that sometimes you can't even climb the safety fence," he said.
"People don't respect the bull, they take pictures, they provoke the bulls.
It is not a game, they are animals that kill, you have to run with your head, conscious of what you are doing."
A 32-year-old Spanish man was gored to death on August 8 near the central city of Toledo after being gored in the neck while filming a bull run.
The previous month a French tourist was gored to death while trying to film a run near Alicante with his mobile phone.
The Spanish town of Villafranca de los Caballeros, some 120 kilometres south of Madrid, made headlines last month when its newly elected socialist mayor decided to use its subsidy of €18,000 ($20,500) for an annual bullfight towards books and school supplies.
After May's local election saw leftists take power in several municipalities across Spain, the town is one of about a dozen that has begun questioning whether public funds should be used for bull events.
Madrid's new mayor, Manuela Carmena, has vowed that "not one euro of public money" would go in funding bullfights while several towns are mulling referendums on the issue.
By Laurence Boutreux