Peel Airports has invested £600,000 to replace and upgrade the airport's approach lights for runway 27 at the eastern end of the airfield.
Some 230 new lights have now been installed on 142 poles to replace those fitted some 20 years ago, which has taken over five months to complete.
The approach lights for runway 27 at Liverpool John Lennon Airport help to guide another arriving aircraft onto the runway.
Peel said the new approach lights will ensure that appropriate aircraft can continue to land in Category III landing conditions, which are associated with poor visibility.
The work was carried out by airfield lighting experts Edward Dewhurst, which experienced severe working conditions due to the cold weather in early December.
Marcus Scrafton, head of development at Peel Airports, said: "The previous approach lights had just about reached the end of their life, so it was important that we replaced these landing aids.
"As with any major works at an airport, we don't have the luxury of replacing them all at one time. With aircraft movements throughout the day, the contractor has to work round the times of any arriving aircraft, so this has been a difficult job to complete. We expect to see these new lights helping our airline customers land at Liverpool for the next 20 years."