Labour’s General Secretary Iain McNicol said it was the party’s largest ever development programme.
Announcing the project at the opening of the Labour Party Conference in Liverpool, he said it was a fitting memory to the mother-of-two who was a champion of international feminism.
Mrs Cox, the MP for Batley and Spen, died after she was shot and stabbed in Birstall in June.
Mr McNicol told the conference: “Today, following discussions and conversations with Jeremy (Corbyn), I’m pleased to announce the Jo Cox Women in Leadership Programme - a brand new mentoring scheme delivered in partnership with the fantastic Labour Women’s Network.
“Over the next five years we will train over 600 future women leaders, our biggest ever mentoring and development programme.
“Jo was a true champion of women in leadership roles and international feminism and this programme will create a generation of women who can continue Jo’s fight in local government, in parliament and crucially in their communities, a fitting tribute to Jo’s life and work.”
Former soap actress Tracy Brabin has been selected as Labour’s candidate for the by-election sparked by Mrs Cox’s death, which will take place on October 20.