Officials say heavy rainfall triggered rockslides, causing debris to fall into the roadway on Saturday.
The closure includes a 2-and-a-half-mile stretch of the highway south of Big Sur at Fuller Point to Ragged Point in San Luis Obispo County.
Maintenance teams are still assessing damage in the area before they are able to clean up the debris.
Officials are hoping for a full reopening by the end of the day on Thursday, December 8.