The ban will last for three weeks, starting from Monday until December 20.
The Los Angeles County Department of Public Health said that all 10 million residents are asked to stay as home as possible and wear a face mask when they come out.
All playgrounds and cardboard will be closed, but the beaches, trails and parks will be open to groups living in the same house.
This order reduces the maximum occupancy by 35% for essential businesses and 20% for non-essential businesses, personal care services and libraries.
Businesses operating outdoors including fitness centers, zoos, botanical gardens and batting cages are reduced to a maximum of 50% capacity.
The order exempts outside church services and protests, which are constitutionally protected rights, the county said.
But the Los Angeles County Sheriff Department said it would not enforce the new stay home order, instead relying on voluntary compliance.
The sheriff’s department said in a statement to CNN, “Since the first stay home order was issued in March of this year, we have focused on education and voluntary compliance.
“We trust the community and rely on people to assess risk and take precautions as appropriate.”
Los Angeles County, the most populous in the US, recently recorded a record number of new Kovid-19 infections and the most deaths in months.
The county confirmed 395,843 cases of Kovid-19 and as of Sunday there were 7,639 deaths. The county has a 7-day average test positivity rate of 6.9%.