Education Secretary Ruth Kelly was struck with an egg as she left a court on Monday after the case of a protester who had targeted her previously.
Ruth Kelly was due to give evidence at the protester's trial
Ms Kelly was hit on the head with the egg outside Salford Magistrates' Court.
Greater Manchester Police charged Michael Downes, 43, of Foxfield Road, Wythenshawe, Manchester with common assault on Monday evening.
A GMP spokeswoman said Mr Downes was due to appear at Salford Magistrates on Tuesday.
Ms Kelly was due to give evidence against Fathers 4 Justice protester Simon Wilmot-Coverdale, but he changed his plea to guilty at the hearing.
He admitted using threatening behaviour towards Ms Kelly at a meeting in her constituency of Bolton West last April, in which she was hit by an egg.
Wilmot-Coverdale was given a two-year suspended sentence, and ordered to pay £250 compensation to Ms Kelly, and £450 court costs.
As she left court Ms Kelly ducked, trying to avoid the egg as it was hurled at her.
She said: "This is just one of those things that comes with being a politician."
Witnesses said Ms Kelly looked shocked when the egg broke on the back of her head.
Wilmot-Coverdale, 35, from Flixton, Greater Manchester, admitted being part of the earlier attack on Ms Kelly when an egg was also thrown.
He was one of two men who ran at her as she arrived for a public debate at a Methodist church in her Bolton West constituency before the general election last May.
One of the attackers tried to place metal handcuffs around her wrists but was stopped by members of the public and another candidate.
In her written statement to the court, Ms Kelly said she had suffered a bruise to her arm in the attack.
The second attacker has not been identified.