Debate has already started over what should happen if the Premier League, which has been suspended until 3 April, cannot resume.
Liverpool is 25 points clear at the top – Manchester City has played one game less – with nine matches remaining in the season.
But Shearer, the top goalscorer in Premier League history, said there was no way Liverpool should be crowned champion if the campaign is not completed.
"If, and it is a huge if, the season cannot be completed then there is no way you can have a winner or loser," he wrote in The Sun. "As harsh and as horrible as that would be for some clubs, none more so than Liverpool, it is the only outcome.
"If you cannot complete the fixtures then you cannot go handing out titles or consider relegating anybody."
Liverpool is just two wins away from wrapping up what would be its first league title since 1990.
Shearer said while it was obvious Jurgen Klopp's men were set for the title, it could not be awarded.
"For Liverpool, it would be incredibly harsh," he said. "But I cannot see how it would be fair to hand them the title – despite the fact it is obvious nobody is going to catch them.
"They only need six points to wrap it up but they haven't got them yet so for that reason it has to be declared null and void.
"It would be very different if the season was suspended after they had got the points to win it.
"But they haven't and however horrible a scenario it would be, it's the only option."