Out of the 20, at least three were declared to be critically injured.
The incident occurred in the 17th minute of the match in the stand containing the travelling Lille supporters, after the visitors had taken the lead.
The French emergency services confirmed that several supporters were taken to the hospital following the incident, The Guardian reported.
Amiens tweeted: "Our hearts are with the injured. We hope they are not very seriously hurt."
Amiens' Stade de la Licorne holds about 12,000 people.
The match delegate, Noel Mannino, followed up by saying, "In light of the events, and given the fact that about 20 were injured, three of them seriously, it has been decided that the game would not resume." (ANI)