The Legally Blonde star will executive produce a contemporary take on the Charles Dickens novel, according to The Hollywood Reporter.
The update - known simply as Expectations - will follow a small-town girl who moves to San Francisco, but struggles to fulfil her dreams until a mysterious benefactor steps in to help.
Lethal Weapon 4's J Mills Goodloe will script the hour-long drama and also executive produce alongside Witherspoon.
The original Dickens work - first published in serial form between December 1860 and August 1861 - follows the story of Pip, an orphan who finds his life changed by a fateful encounter with an escaped convict.
Previous adaptations of the story have included a celebrated 1946 film version starring John Mills and Alec Guinness, Alfonso Cuarón's 1998 update with Ethan Hawke and Gwyneth Paltrow, and last year's three-part BBC serial starring Ray Winstone, Gillian Anderson and Douglas Booth.
The CW is developing a number of pilots based on existing properties this television season, including an Alice in Wonderland update, a new version of Sleepy Hollow and a Wonder Woman adaptation.
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Watch a clip from the BBC's Great Expectations below: