The former Home Secretary will tell a fringe meeting at the Labour conference that radical changes are required to rebalance the public finances.
Under current rules, all parents regardless of income receive weekly child benefit payments.
But there is a growing political feeling that better-off families should not be getting such benefits.
Vince Cable, the Lib Dem treasury spokesman, has suggested means testing child benefit.
Mr Blunkett will say that the benefit should be taxed, along with winter-fuel payments to pensioners.
The money raised from better-off parents and pensioners could be used to fund Labour’s child poverty plans, he will say.
Mr Blunkett will also take aim at the replacement for the Trident nuclear weapons system.
Gordon Brown, the Prime Minister, has said that when Trident is replaced, the number of nuclear-armed submarines should be cut from four to three.
But Mr Blunkett will go much further, suggesting that Britain’s entire nuclear weapons programme should be dropped.
Mr Blunkett’s contribution comes as all major parties look at ways of saving money to pay down the £1.4 trillion national debt Labour is running up.
Some senior Tories are also looking at universal benefits like child benefit and asking if they should be restricted to save money.
There is also talk in Tory circles about the nuclear deterrent, but David Cameron, the Tory leader, has made clear he would not give up nuclear weapons.