Although he said it would be hard to quantify how much more the central bank needed, the Reserve Bank needs an "appropriate-sized team of specialists, rather than an army of generalists".
The Reserve Bank's Deputy Governor Geoff Bascand said the bank needs roughly 15 more people to assist in its regulatory functions.
National's Finance spokeswoman Amy Adams said it was concerning that the Reserve Bank was saying it was under-resourced when it had delivered a $430 million surplus back to the Crown in the form of a dividend.
"We would argue to say that you're under-resourced and looking after our banks and insurance agencies is pretty significant."
She challenged Orr to officially ask the Government for more funding for staff.
"They're a cash-cow for the Government right now and yet they're not being given the resources they need."
Finance Minister Grant Robertson said issues around the Reserve Banks staffing levels had been raised with him in the past.
He said he would be looking into this and would "certainly consider it" if Orr formally approached him, asking for more funding for staff.
"They're not unlike any other agency; they're always on the lookout for additional staffing."
He said officials were in the middle of the second phase of the review of the Reserve Bank which looks specifically at this type of issue.
"This will help inform any decision we make about staffing – but obviously we want our regulatory agencies to be in a position to be able to do their jobs."
Meanwhile, Robertson appeared unconcerned with a recent leak of Budget information.
Yesterday, the Herald revealed Ministers had been ordered to review their portfolios in preparation for the next Budget and identify at least 1 per cent of expenditure which is not in line with the Government's objectives.
The information came from a leak, obtained by National.
"Leaks happen from time to time in the public service," Robertson said.
He would not comment on the specifics, but he said he had been clear the Government is always looked for value for money.
He said he was "very confident" the leak did not come out of his office.
The Treasury is looking into where the leak came from, he said.
Treasury has been approached for comment.