The air base will be built at the site in Incirlik where the Bundeswehr (German army) is currently flying reconnaissance and refuelling missions into Syria, according to a planning paper from the Defence Ministry seen by Spiegel.
The new extension to the Turkish base will include an air controller centre for the German aircraft, accommodation for soldiers and a completely equipped combat headquarters.
Germany is also reportedly in discussions with Ankara about a treaty for stationing German soldiers on Turkish soil for long-term deployments.
German Tornado jets have been stationed in Incirlik for several months, ever since Berlin agreed in the wake of the Paris terror attacks in November 2015 to support France in its military campaigns against Isis.
The Tornadoes use high definition cameras to take detailed pictures of potential bombing targets before Nato allies fly bombing missions, and fly almost daily missions.
The Bundeswehr also has Airbus air tankers at the Turkish airbase to refuel German and allied aircraft and a total of around 200 soldiers stationed there.
The plans foresee that in the coming six months Germany will invest around €10 million in an air controller area which is especially for the German aircraft, a further €15 million in accommodation for around 400 soldiers, and €34 million in building a combat headquarters from where missions will be coordinated.
The Bundeswehr also wants build a care facility for soldiers equipped with a cafe and leisure activities area, which the planning paper estimates would cost €4.5 million.
Most of the projects should be completed by summer 2017.
While up until now Turkey was responsible for providing facilities for its NATO partners, the German Ministry of Defence expects the military campaign against Isis to drag on, and therefore believes that more permanent solutions are urgently necessary.
The Bundeswehr will have to work with local contractors on the building projects, but the budget has already been approved in Berlin with the hope that building work can begin as quickly as possible.
One opposition politician, speaking to Spiegel, expressed surprise at the speed with which Germany's initial reaction to the Paris attacks has turned into a long-term military presence in Turkey.
“Although this mission against Isis came so suddenly, Defence Minister [Ursula] von der Leyen seems to want to dig in for the long term,” commented Tobias Lindner from the Green Party.
Linder called on the government to immediately release all the details of their plans to build the air base in southern Turkey.