NHS Highland charges £5 for one copy and £10 for three copies.
Following an investigation, SNP MSP Kate Forbes found that the board is the only one in Scotland to ask for a fee.
NHS Highland said charges have been in place for some time and the money covered the cost of high quality paper, but it would now review the practice.
Twelve out of 14 health boards issue one copy free, while NHS Lothian requests a voluntary donation, according Ms Forbes' investigation.
She said: "Seeing your baby for the first time on a scan at the hospital is an exciting and happy moment for mums and dads-to-be, particularly when you can see their little hands and feet moving for the first time.
"But it is unfortunate that pregnant mums in the Highlands are the only women in Scotland having to pay £5 for a photo of their baby at their antenatal scans."
A spokesperson for NHS Highland said: "NHS Highland can confirm that we do charge £5 for a copy of an antenatal scan and £10 for three copies.
"The antenatal scans are printed on high quality photographic paper for personal use by expectant parents, and the current charges were put in place after an increase in 2014.
"Charging for scanned photographs has been in place for a number of years, but in the light of the current information we will now undertake a review of this practice."
Ms Forbes said she was pleased the health board is to review the charges.
She added: "The matter came to light after I heard of a woman who had moved from Glasgow, where scan photos are free, to the Highlands, where she had to pay.
"My concern is the disparity between all the other health boards and NHS Highland."
A health board is to review its practice of charging for copies of antenatal scans after being told it is the only Scottish board that does so.