Systems and methods for preheating fuel in a gas turbine engine are provided. In one embodiment, a system may include a gas turbine engine, a fuel line in fluid communication with the gas turbine engine, a gas turbine compartment disposed about the gas turbine engine, and a first conduit in fluid communication with the gas turbine compartment. The first conduit may include ventilation discharge air from the gas turbine compartment. The system also may include a first heat exchanger in communication with the fuel line and the first conduit. The first heat exchanger may be configured to exchange heat between the fuel and the ventilation discharge air from the gas turbine compartment.