The Saddlers have accepted Halsall's resignation just 24 hours after he was at the Banks's Stadium talking about a sponsorship boost from Walsall Housing Group and his high hopes for the club's youth set-up this season.
Halsall, who has been with Walsall for 10 years in a variety of roles, is widely regarded as one of the best youth-team coaches in the midlands and turned down the chance to become Academy manager at Stoke back in February, shortly after having a first resignation request rejected.
He will now take up the role of assistant Academy manager/Under-18's coach at Molineux.
Walsall chief executive Roy Whalley told the club's official website: "It was disappointing to receive his resignation at this time. However, we have decided not to stand in Mick's way. His resignation has been accepted and he will be allowed to leave the club and take up his new position after the end of this week."
Manager Chris Hutchings added: "He has done a wonderful job and he will go with our best wishes. He has produced some good players for this club over the years and we are sorry to see him leave."