Local media later reported another worker had died of a heart attack at a convention centre next to the stadium in Manaus where England will play their opening match against Italy.
The state's public prosecutor's office asked a judge to suspend work on the Manaus stadium until safe working conditions could be guaranteed, though such requests are not often granted in Brazil.
Marcleudo de Melo Ferreira, 22, died in a hospital after falling when a cable broke and became the fifth person to die while building the World Cup stadiums.
FIFA said it learned of the death "with great sadness". The death of Jose Antonio da Silva Nascimento, 49, from a heart attack led the local construction union to threaten to strike, possibly resulting in further construction delays.