National MP Paul Foster-Bell denies being a bully following claims from a former staffer that he is.

A former staffer in National MP Paul Foster-Bell's office has accused him of being a "bully".

A dozen staff have left the list MP's Wellington office in the last three years - the taxpayer funds two full-time positions for him.

Newshub reported 12 staff had left since May 2013 because of an untenable working environment but Foster-Bell said he thinks he's a good boss.

He said his staff had left for "all sorts of reasons" and wouldn't comment on allegations of bullying.

A former staffer said, "Paul denied telling HR that he demanded my resignation on a certain date then refused to acknowledge he had done wrong. The fact is, he's a bully".

When asked by Newshub if he was a bully, Foster-Bell replied, "of course not".

Taxpayers fork out $180,000 for backbencher MPs and also pick up the bill for their two staff.

Another former staffer, who also wished to remain anonymous, told Newshub, "I've had my name tarnished and have borne the brunt of his incompetency as a manager. He's good at going to events, but the nuts and bolts of being a manager is where he's lacking."

Foster-Bell is deputy chair of the Government Administration select committee and also sits on the Local Government and Environment select committee.

In the 2014 election he stood in Wellington Central for a second time and was beaten by Labour's Grant Robertson.

Prior to joining Parliament Foster-Bell was a diplomat. His last assignment was as Deputy Head of Mission at the New Zealand Embassy in Saudi Arabia.