Jubilee Hall Play Park, in Lupset, reopened last week following an extensive makeover which saw the installation of new, inclusive play equipment.
But less than a week later, the park has been damaged by a fire.
Councillor Michael Graham, who represents the area, described the damage as "absolutely soul destroying", and promised to investigate the cause of the blaze.
He said: "Unfortunately there have been acts of vandalism and damage to the children’s play area at Jubilee Hall. To see this happen after less than a week is absolutely soul destroying.
"Since reopening there have been dozens of families and young children coming from all over to use the new equipment. Parents have contacted me to say how happy they are to see money being put into the area.
"Children in Lupset deserve a decent place to play and they deserve to be invested in.
"Local councillors will be liaising with West Yorkshire Police and Jubilee Hall to review the CCTV footage of the play area. We have also contacted Wakefield Council to see what can be done to clean the area up."