The money will go towards launching proven parental conflict provision in more local areas and improving the quality of family services already in place.
Meanwhile, all local areas will be helped to train frontline practitioners in identifying parental conflict and referring families on to appropriate services.
The DWP said research suggests that children's emotional, behavioural and educational success is strongly influenced by their parents' relationship, with children whose parents are in long-term, unresolved conflict with one another - whether or not their parents are together - being less likely to do well in school and in adulthood.
It added that a child is also more likely to do well if they have a close, supportive relationship with their father and this is made more difficult when separated parents are in conflict. An estimated 300,000 workless families are potentially affected by the issue.
The new initiative, set out in the government policy paper Improving Lives: Helping Workless Families, published today, will work alongside the Troubled Families Programme to support local areas across England to improve the effectiveness of their family services.
This will be done by drawing on lessons from the DWP's Local Family Offer trial which has supported 12 areas to link parental conflict support into other local services for families.
"We plan to develop [a] cost-benefit framework… to help demonstrate more clearly for local commissioners the savings that could be made to the public purse from investing in reducing parental conflict," the policy paper states.
"This will demonstrate the importance of tackling parental conflict to promoting children's health and educational outcomes, as well as other priorities for local commissioners.
"We know, for example, that local authorities commission parenting classes, but these have limited impact if parents are in conflict."
The DWP said it will shortly be launching an opportunity for organisations to bid to deliver evidence-based work to reduce parental conflict in order to increase the supply of quality services available to local commissioners.
"Successful bidders will deliver help face-to-face for workless families using interventions which have been shown to make a difference to the quality of inter-parental relationships, and parents' ability to collaborate," the policy paper adds.
"Alongside this we will fund more training for practitioners to deliver proven interventions, including Troubled Families key workers, so that there is more help available to meet the needs of families."
The government has also announced that the next stage of its flagship Troubled Families Programme, which is currently working to help disadvantaged families with complex needs, will have a greater emphasis on tackling worklessness and the issues associated with it - such as parental conflict and problem debt.
Work and Pensions Secretary, Damian Green, said: "I don't want any child to be defined by the circumstances of their birth. Every child should benefit from a strong relationship between their parents - whether they are together or separated.
"Today marks the start of new support to help families overcome the problems they face to make sure that every child can go as far as their talents will take them."
Carey Oppenheim, chief executive of the Early Intervention Foundation, said: "We are familiar with interventions designed to support the adult couple relationship, and with other interventions designed to support parenting.
"Today's announcement marks an essential and long overdue shift to focusing on the benefits for children's development and wellbeing that can come from effective family support interventions."