It follows a push from psychiatrist and psychologist groups to lift support for people who have the disorder.
Asked if he supported expanding the scheme to include people with ADHD, NDIS minister Bill Shorten said: "No."
"I don't think that ADHD should automatically give you a ticket into the NDIS," he told ABC radio on Friday.
"I don't think we should be just saying that if you have a diagnosis, you automatically get entry to the scheme."
Mr Shorten said the test for eligibility was not just about a diagnosis but involved considering how a person was affected by their disability.
"There are a small number of people whose primary diagnosis is ADHD because it clearly affects them a great deal," he said.
The cost of the NDIS is expected to blow out to about $60 billion a year by the end of the decade and there has been a push to make the scheme more financially sustainable over the long-term.
The Royal Australian College of General Practitioners has reaffirmed its call for GPs to play a greater role in the diagnosis and treatment of ADHD.
"Too many people with ADHD are not getting the help they need, when they need it," RACGP president Nicole Higgins said.
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