Police were alerted to the incident when they received a call about the man at 4:40pm.
When officers arrived at Hohenzollern Bridge, the man had asked for an interpreter. After an interpreter had been able to contact him, he climbed down.
"He told us he didn't want to kill himself," said a federal police spokesman.
The asylum application of the 29-year-old Iranian man had previously been rejected, a police spokesperson said. While on the bridge, the man had thrown notes down with poems written in Arabic script on them.
The protest action had large consequences for rush hour traffic as the Hohenzollern Bridge is particularly important for rail routes in and out of the west German city.
The bridge was subsequently closed for two and a half hours in the afternoon on Wednesday. According to Deutsche Bahn, the incident caused many diversions and partial disruptions because trains had to turn around to avoid using the bridge.
Eyewitnesses reported that the platforms at Cologne's main station were packed with people during the closure. Rescue workers from the city's fire brigade were also deployed and ships in the Rhine River under the bridge had to stop during the operation.
The asylum seeker has meanwhile been released again and, due to the disruption he caused, can expect to face a legal complaint.