The campaign will be led by recently appointed marriage and family life co-ordinator, John Anthony, who is assisted in lobbying, media and stakeholder relations work by the church's communications directorate.
Director of comms Mark Morley said lobbying work surrounding the Adoption Bill, which is set to become law this year, was a priority.
In May MPs gave the green light to an amendment in the bill allowing unmarried couples, straight or gay, to adopt.
Morley said: 'Taking away the primacy of marriage from adoption procedures could create all sorts of problems. What happens legally if two people both adopt and they then split up?'
Other campaigning on the issue of marriage includes media relations work to highlight its significance as an institution, and not just specific to the Catholic religion.
Anthony said he will also be liaising with marriage guidance and preparation groups of all denominations to gain interfaith backing, 'to counteract the dire social and economic effects of the disintegration of married life.'
He added that this would be a long-term project.
Morley added that this latest campaign is 'part of a longer-term commitment to act as a positive and pro-active social organ, identifying areas within society that are sometimes troublesome and finding imaginative ways of bringing care, support and wider understanding'.
Earlier this year the church pledged greater transparency regarding potential child sex abuse scandals. This was announced amid accusations of a cover-up during revelations of paedophilia in the church in the US (PRWeek, 3 May).