Twenty-two of the cases had been raised by the Australian Human Rights Commission, which last year said there was a "high risk" Indonesians under the age of 18 were being held in adult prisons, and two others by Indonesia.
"Minors don't belong in adult jails and I am taking seriously the concerns of the Australian Human Rights Commission and the Indonesian government," Nicola Roxon, the attorney general, said yesterday.
"The individuals who are part of this review were all legally represented, 14 of them pleaded guilty, and only three contested age in court proceedings.
"Ultimately, it is the courts which determine the age of people-smugglers - but age determination is not an exact science, which is why I've asked for this review."
As a rule, Australia does not prosecute minors accused of people-smuggling and Ms Roxon said prosecutors give the benefit of the doubt in cases where age cannot be clearly established.
But advocates for Indonesians hired to crew asylum-seeker boats have complained that mistakes about their clients' ages, sometimes as a result of wrist X-rays, had resulted in children being placed in adult jails.