The gender pay gap in the medical professional is "unacceptable", according to National Party health spokesperson Dr Shane Reti.
A New Zealand Herald investigation has revealed female doctors earn up to $73,000 less than their male counterparts, despite working the same hours and responsibilities.
In specialist medicine, the gender pay gap is an alarming 12.5 percent.
Only two of the country's 20 DHBs had senior female doctors being paid more than their male colleagues.
Tairāwhiti DHB paid women $31,696 more, and in Canterbury, senior female doctors received an additional $316.
Dr Shane Reti is urging DHBs to address the issue.
"Any gender pay bias in the medical profession is unacceptable," he told Newshub on Saturday.
"There needs to be serious scrutiny of how prevalent this is, the circumstances and attention to solutions going forward."
The data, obtained under the Official Information Act, shows there are nearly 1200 more senior male doctors in NZ's public hospitals compared with female doctors.
There are currently 3459 male senior doctors in New Zealand, compared to only 2276 female doctors.
While surgery is the highest-paying medical profession, it has the lowest proportion of women.