Wearing jeans and a casual black top, the actress came out to run errands in Santa Monica, reported Daily Mail.
The 36-year-old and her husband Jim Toth welcomed their first child together on September 27.
It is Witherspoon's third child. She also has two other children - daughter Ava, 12, and son Deacon, 8, with ex-husband Ryan Phillippe.
Witherspoon and Phillippe split in 2006 after seven years of marriage.
