Shirley Beauchamp, 37, and her husband Stirling, 43, were outraged when Georgina's head Andrew Holt wrote to them saying he was worried she could be getting overweight.
The head from Tewkesbury primary, in Gloucestershire, urged the Beauchamps to get some diet and fitness advice for their six-and-a-half stone daughter after she was said to have struggled to get out of the swimming pool during a PE lesson.
Now Mr and Mrs Beauchamp have decided to transfer Georgina to another primary school amid claims their daughter was being picked on.
Mrs Beauchamp said Georgina's weight was down to her metabolism and she did not have a problem.
Sam Roffe, a spokeswoman for Gloucestershire County Council, said: "Parents have theright to choose whichever school they wish for their child as long as it has space. Georgina's parents have obviously felt the need to give her a new start and we wish her all the best for the future."
Mrs Beauchamp, who has an 11-year-old son Kenneth and daughter Elizabeth, 13, added most of the family was on the larger side.
But the county council defended the decision to raise the matter and said it was sparked by fears for the youngster's health.
The British Nutrition Foundation estimates the average five-year-old should weight between three and three-and-a-half stone.
Earlier this week, Sir Michael Bichard, permanent secretary of the Department for Education and Employment, defended the headteacher's action. He said: "It is something that should be done sensitively, but does need to be done in certain situations."