Princess Anne, patron of the Firefighters’ Memorial Trust, visited the 9ft (2.74m) tall granite monument at Brixworth Country Park.
She has also visited the police’s new criminal justice centre in Northampton.
County councillor Andre Gonzalez de Savage said the “important” memorial recognised firefighters who served in Northamptonshire.
The memorial was commissioned by the fire service to commemorate and honour Northamptonshire’s firefighters and to provide a quiet place for reflection for people who have been affected by fire in any way.
It was dedicated by The Right Reverent John Holbrook, Bishop of Brixworth and was formally unveiled by Princess Anne, who is also a patron of the Firefighters’ Memorial Trust.