West Mercia Police told the Hereford Times of its attendance estimate ahead of the Bulls' Southern Football League clash with St Neots Town.
Police say officers will be on duty around the ground, adding they are aware of a planned protest against the club's ownership shortly before kick-off.
The Hereford United Supporters Trust (HUST) has today contacted its members urging protesters to be "peaceful and lawful".
"HUST members are welcome to join the protest to show their displeasure at the current situation, but we implore everyone to do so in a peaceful and non-confrontational manner," said the statement.
"No matter the depth of feeling around Edgar Street, anyone who chooses to enter Edgar Street to watch the game has the right to do so without intimidation.
"As much as we ask that of the protestors, we also ask that those who have indicated they will attend the game respect the right of the protestors to make their point peacefully."
Those attending the match will only be able to watch from the Meadow End and Merton Stand as part of clauses in the club's ground safety certificate which was issued yesterday.
A maximum of 1,000 fans can be let in the ground.