The plaque will feature a coat of arms that her children Cuillin, six and Lejla, four, helped create.
The design features the motto "More in Common", inspired by Mrs Cox's maiden Commons speech in 2015.
Mrs Cox, the Labour MP for Batley and Spen, was murdered outside her constituency office in Birstall, West Yorkshire, by Thomas Mair in June 2016.
The plaque design will include representations of her support for women in politics and the Cox family's love of the water and mountains.
It is due to be unveiled on 20 May as part of a "family day" in Parliament, when MPs and staff will be invited to bring their children into the Commons chamber.
Speaker John Bercow will answer questions from children and then host a party - the first of the "Great Get Together" events the Jo Cox Foundation is backing to mark the anniversary of her death.
Mr Bercow said: "Jo Cox was recognised, both inside the House and by all who had the privilege to know her, for her empathy, conviction and her passion for what she believed in.
"It will be an honour to host the first of the Great Get Togethers in her memory. Jo's life and legacy will not be forgotten."
Plans to host thousands of street parties across the UK under the banner The Great Get Together were revealed in February by Mrs Cox's widower Brendan.
Events will be held from 16-18 June, with members of the public encouraged to host gatherings such as street parties, picnics and coffee mornings.
A memorial plaque for murdered MP Jo Cox is to be unveiled in the House of Commons.