Northants Fire say a blaze at Kettering Town’s old Rockingham Road ground on Tuesday is being treated as a suspected arson.
Four fire crews attended the incident shortly after 4.20pm after smoke was spotted coming from the dilapidated stadium.
The blaze caused “significant” damage to the ground floor of the seating area of the main stand.
A Northants Fire spokesman said: “There was significant fire damage to the ground floor of the grandstand seating area, and some smoke damage.
“The cause is being treated as deliberate.”
Kettering councillor Michael Brown (Ind, Brambleside) says the stadium needs to be properly secured to prevent further incidents.
In a letter to the authority’s service head for planning, he said: “I would like to make a formal request to the planning department that they seek from the land owner of Rockingham Road Football Stadium that they secure their property properly before their is a serious injury or fire at the property.
“Last night we saw another break-in and another incident of arson at the property.
“The landowner must take steps to prevent this from happening.
“I have written to you about this property before on behalf of residents.
“Please can you let me know what action has been taken to date on this property and what possible action the council can legally take in regards to this?”
Witnesses to the incident should contact police on 101 or Crimestoppers anonymously on 0800 555111.