The Brazilian government halted work on two temporary tribunes for Sao Paulo's World Cup stadium after the death of another construction worker, media reports said.
A new inspection of the Corinthians club stadium to be used for the World Cup opening match between Brazil and Croatia on June 12 was to be carried out on Tuesday.
The worker died on Saturday after an eight metre (26 feet) fall. Three workers have now been killed during the Sao Paulo construction and seven in World Cup work across Brazil.
According to press reports, the man who died on Saturday may not have been wearing safety equipment. His employers have denied this.
The regional labour department ordered construction work halted on the two temporary tribunes until the company carrying out the work installs safety nets.
The two tribunes have a capacity of 20,000 people and the Brazilian organisers are racing to get the stadium ready on time.
Fast Engenharia, the company carrying out the construction, said in a statement to the G1 news website it would carry out a technical inspection Tuesday before making any comment on the impact of the latest accident.
FIFA has already extended the deadline once for Sao Paulo. It is now scheduled for delivery in mid-April, though organisers admit the work will not be completely finished.
FIFA president Sepp Blatter said last Thursday that the stadium would be ready for the opening match.
In November, two workers were killed at the Corinthians stadium when a crane fell.
Brazilian authorities are also wrangling over who will pay an estimated 26 million dollars for temporary tribunes in World Cup stadiums.