The city is accessed from around the world via the Frankfurt Airport (Flughafen Frankfurt am Main) which is located 12 km (7 mi) from the city centre. The airport has three runways and serves 265 non-stop destinations. It ranks among the world's top ten airports and is the biggest cargo airport in Europe. The airport also serves as a hub for German flag carrier Lufthansa. Depending on whether total passengers or flights are used, it ranks as the second or third busiest in Europe alongside London Heathrow Airport and Paris Charles de Gaulle Airport. Passenger traffic at Frankfurt Airport in 2007 was 54.2 million. The airport can be reached by car or bus and has two train stations, one for regional and one for long-distance traffic. The S-Bahn lines S8 and S9 (direction "Frankfurt (Main) Hbf", "Offenbach Ost or "Hanau"), departing at the regional traffic station take 10–15 minutes from the airport to the Central Station and the city centre, the IC and ICE trains departing at the long-distance traffic station take as well 10–15 minutes.

Despite the name, Frankfurt Hahn Airport (Flughafen Frankfurt-Hahn) is not located anywhere near Frankfurt but is instead situated approximately 120 km (75 mi) from the city in Lautzenhausen (Rhineland-Palatinate). This airport can only be reached by car or bus. An hourly bus service runs from Frankfurt Central Station, taking about 1 hour and 45 minutes. Last year over 4 Million Passengers used this airport in order to use Low Cost Airlines like Ryanair.

Frankfurt Egelsbach Airport is a busy general aviation airport located south-east of Frankfurt International Airport, near the town of Egelsbach.