MEETING Santa Claus for the first time was meant to be a jolly experience for Cameron Sleeth, 6.

But the excitement of meeting St Nicholas turned into a nightmare his mother wishes she could forget.

Tammy Sleeth said her two sons, Cameron, who has Asperger's syndrome, and Liam, 7, who has autism, were thrilled to have the chance to hear Santa say "ho, ho, ho, merry Christmas" and tell him what presents they hoped for this year.

But when she took her family to Logan Hyperdome, in Shailer Park, Queensland, on Thursday, what was planned to be a fun time turned into a distressing turn of events.

In a scene reminiscent of the film Bad Santa starring a foul-mouthed Billy Bob Thornton, the shopping center Santa made a mockery of her sons including Cameron who was wearing a T-shirt that read, "think before you judge, I have autism".

"The boys went up to Santa, my six-year-old was so excited to see Santa and he was doing a little dance in front of Santa, I thought it was cute, he was happy," she said.

"Then Santa looked at Cameron's shirt and looked at me and said 'has he had his medication tonight?' and I said 'excuse me?'. I was just disgusted."

They were among dozens of children lining up to meet Santa.

Mrs Sleeth, from Boronia Heights south of Brisbane, said the boys started to tell Santa what they wanted for Christmas but she was left shocked at his response.

"They started saying what they wanted and then about two or three seconds later he said to them 'what about a jail cell?'," she said.

"After he said that I thought I didn't hear right and then he said it again, 'do you want a jail cell?'

"My six-year-old responded, 'jail cell' and I was mortified, I thought how dare you, he's not playing up, he's not being naughty."

Mrs Sleeth said she was in tears after the incident and doesn't want to take her sons to meet Santa again.

"I'm glad Cameron didn't understand it and even after Santa said it Cameron was still giving him hugs," she said.

"I certainly knew what he was going on about and I thought that's disgusting, how dare he insinuate my child needs to be institutionalised."

Centre manager Rob Mansfield said the man involved in the incident was being investigated and was no longer working in the center.

He said the Sleeths where being sent a package which included children's toys.