Mrs Reagan will deliver a speech on the subject at a Beverley Hills fundraiser sponsored by the Juvenile Diabetes Research Foundation this weekend.
While Mrs Reagan, whose husband has Alzheimer's disease, has never publicly contradicted Republican presidents while in office, she has made known her views on the subject and her disappointment with the current administration's policy.
Her attempt to highlight the topic comes in a week when new research has supported the theory that stem cells from embryos have a greater potential to cure diabetes than stem cells from adults.
In August 2001 President George Bush announced that research would be restricted to ensure that embryos could not be destroyed with funds from the tax payer.
While he was contemplating the issue three years ago, Mr Bush was contacted by Mrs Reagan saying she hoped he would do what he could to spare other families what hers had suffered and this could be a great part of her husband's legacy.
Michael J Fox, who has Parkinson's disease and runs a foundation promoting stem cell research, will present Mrs Reagan with an award at this weekend's function.
Last week 206 members of Congress, including some Republicans and almost 40 opponents of abortion, signed a letter urging Mr Bush to finance studies on surplus embryos at in vitro fertilisation clinics. The Republican Senate leader, Bill Frist, who played a key role in encouraging Mr Bush to take up the issue in 2001, said he backed the current policy but believed it was time for a review.
"It's been three years and I think it's time to do it," said Mr Frist, a heart surgeon. "I'm very interested in answering the question whether or not scientists are really leaving this country in droves because of the limitations on research."
Meanwhile John Kerry, who was an early supporter of stem cell research, has been lambasting the Bush administration on the issue, accusing him of choosing ideology over science.
Mrs Reagan's speech coincides with an apparent breakthrough in research into diabetes using embryonic stem cells. In the latest issue of Nature, a Harvard cell biologist, Douglas Melton, argues that only embryonic stem cells can transform themselves into the insulin-producing "beta cells" which are destroyed or fail in around 10% of diabetics.
Mr Melton's team concluded that "embryonic stem cells are currently the only type of stem cell that is unquestionably capable of differentiation into beta cells".
Ronald McKay, a stem cell researcher at the National Institute of Neurological Disorders and Stroke told the Washington Post: "It's a tightly done experiment and the results are clear."
Others contend that the results are questionable given that the tests were conducted on healthy mice rather than diabetic humans.
"To see the effect of stem cells [making beta cells] you may need a more realistic situation like diabetes," said Vijay Ramiya, a researcher at the University of Florida.