The 49ers join the Los Angeles Rams and Los Angeles Chargers as the other NFL teams in California to begin their respective seasons without fans in attendance due to the COVID-19 pandemic.
In a statement, the 49ers said they will continue to monitor the situation with health officials to decide on when fans will be allowed back inside.
The NFL season is set to kick off on September 10 between the Kansas City Chiefs and Houston Texans.
The 49ers are coming off a Super Bowl loss to the Kansas City Chiefs back in February.