New Zealand Post has fired 169 posties in the past three years.
Figures issued to Radio New Zealand show 103 posties have been dismissed for serious misconduct since 2008, 52 for unauthorised absence, eight for theft and six for poor performance.
It says 'serious misconduct' covers damaging company property, failing to deliver the mail, misappropriation of company money and consuming drugs or alcohol on the job.
The company says it has to maintain standards.
NZ Post says the average of 56 dismissals each year is just under 2% of the 3000-or so people who work as a postie in any given year.
The Postal Workers Union, which has 900 members, says the level of dismissals is surprisingly high, especially when compared to other professions.