The incident involved a London Overground service at Enfield Town station during the morning rush hour on Tuesday.
Images posted on social media showed the train remained upright but came off the tracks and stopped just short of hitting a station building.
One commuter said there was “chaos” as services were suspended between Enfield Town and Edmonton Green.
He tweeted: “Just been there & chaos at the door. Train arrived at Enfield Town & crashed into the buffers.
“Fortunately didn’t go through the station window.”
A London Ambulance Service spokeswoman said: “We were called at 8.16am this morning to reports of a train derailed at Enfield Town railway station, Enfield.
“We sent a number of resources to the scene: one ambulance crew, an emergency planning officer, a clinical team manager, two incident response officers, medics in cars, and our hazardous area response team.
“Two people were assessed at the scene for minor injuries, but they were not taken to hospital.”