The most dangerous place to be a postman in the north of the county is Kettering.
Dogs bit 19 posties in the NN16 postcode, which covers the town, during 2008, 2009 and 2010.
In Wellingborough’s NN8 postcode there were 11 dog bites, and one assault by a person.
There were 10 attacks on postmen and women in Rushden’s NN10 postcode – nine by animals and one by a person.
And the safest town to be a postman is Corby, where there were just six bites sustained by postal workers in the NN17 area.
The Royal Mail said it had introduced several measure in recent years to try to combat the problem, including writing to the owners of aggressive dogs to warn them about their animals.
The figures also showed that there were no injuries at all sustained in several postcodes including PE8 which covers Oundle, NN14, which covers towns to the west of Kettering, and in NN18 which covers rural parts of south Corby and north Kettering.
In the LE16 postcode, which covers Cottingham and surrounding villages, plus most of Market Harborough, there were 11 injuries.
Royal Mail also released details of the injuries suffered during the incidents.
Dogs were most keen to bite into the fingers on the right hand, with 10 incidents during the three-year period.
Five dogs preferred the left arm, left hand fingers, right shin and left hand. Three dogs bit left buttocks, but none chose to sink their teeth into a postman’s right buttock.
Bosses at the organisation said they had introduced a range of measures to try to minimise the risk to their employees.
A spokesman said: “The safety of staff is a main priority for the Royal Mail Group and we ensure advice is provided to staff regarding how to reduce the risk of attack.
“Royal Mail and the Communication Workers’ Union have pledged to work together to raise awareness of aggressive dogs.
“Delivery managers are urged to remind their teams of guidelines designed to minimise the risk of attack.
“Protective measures by the business include sending letters to owners of aggressive animals and warning staff where dangerous animals live.
“Our main aim is to prevent attacks. If we feel there is a risk from a dog or any other animal at an individual address we are committed to working with the customer to agree simple steps to ensure we can deliver the mail safely.
“Posting pegs were made available to our staff nationally in May.”
Posting pegs are a gadget, similar to a folding ruler, which allows the postman to put items through the letter box without exposing their hands or fingers to a dog inside the house.