The American study says it has found evidence of children and young people who appeared to have recovered from the development disorder.
But the National Autistic Society said the sample of 34 individuals, aged eight to 21, was so small that it would be 'wrong to jump to conclusions'.
Psychologists in the US concluded that the people they studied no longer suffered symptoms of autism, which makes it difficult to communicate and socialise.
Writing in the Journal of Child Psychology and Psychiatry, the authors said the study 'documents a group of individuals with clear early histories of autism who currently show normal language, face recognition, communication and social interaction, and no autism symptoms'.
They suggested that 'moving off the autism spectrum into normal functioning' was 'a possibility'.
Dr Thomas Insel, director of the US National Institute of Mental Health which supported the study, said: "Although the diagnosis of autism is not usually lost over time, the findings suggest that there is a very wide range of possible outcomes."
However, Dr Judith Gould, of the National Autistic Society, said many children learn coping strategies which could hide the condition from specialists in adulthood.
"This study is looking at a small sample of high functioning people with autism and we would urge people not to jump to conclusions about the nature and complexity of autism, as well its longevity," said Dr Gould.
"With intensive therapy and support, it's possible for a small sub group of high functioning individuals with autism to learn coping behaviours and strategies which would 'mask' their underlying condition, and change their scoring in the diagnostic tests used to determine their condition in this research.
"This research acknowledges that a diagnosis of autism is not usually lost over time and it is important to recognise the support that people with autism need in order to live the lives of their choosing."
She continued: "Getting a diagnosis can be a critical milestone for children with autism and their families, often helping parents to understand their children better and helping them to support their children in reaching their full potential. The importance of diagnosis can therefore not be underestimated."