More than 80 percent of lawmakers responding to a recent survey support revising the organ transplant law during the current Diet session to pave the way for children to receive new organs.
Questionnaires were sent to all 720 Upper and Lower House members, but valid responses were received from only 150.
The low response rate indicates many lawmakers have yet to take a view on the issue, which is closely related to religious and other views about life.
In the 12 years since the law took effect, around 100,000 patients have died because they could not receive transplants, according to the Japan Society for Transplantation.
Some 83 percent of the respondents support amending the law, of which 72 percent said the minimum age of 15 for brain-dead donors in organ transplants should be eliminated.
But less than 50 percent of the lawmakers in the survey agree with recognizing brain death as legal death by revising the current law, which accepts brain death only when a person is ready to become a donor.
More than 30 percent want to keep the existing rule, indicating deep resistance to recognizing brain death as legal death without exception.