The Learjet 25 is an American ten-seat (two crew and eight passengers), twin-engine, high-speed business jet aircraft manufactured by Learjet. It is a stretched version of the Learjet 24.

The Learjet 25 offers an ideal high speed platform for business travel for six to eight passengers. The aircraft's high rate of climb enables it to pass congested flight levels quickly. Typical cruising altitudes are between Flight Level 390 and Flight Level 430 which means the Learjet 25 is capable of overflying most weather systems and congested airspace. With a cruising speed of approximately Mach 0.76, passengers reach their destination in good time.

The cabin interior can be converted to several different configurations to allow for cargo and medevacs. Due to the ease of converting the cabin the Learjet 25 has found a niche as a medevac aircraft. This is achieved by removing the starboard seating to allow for a stretcher, mounting oxygen bottles and intravenous drip equipment. The two flight crew are then supplemented by either a doctor or flight nurse or both. The Model 25C also has an optional two bed sleeping compartment.

Despite being used at lower altitudes and equipped with small landing gear, the Learjet can land on gravel runways if it is fitted with a special "gravel kit". It is possible for gravel from an improperly packed gravel runway to be sucked into the engines causing "foreign object damage", thus the need for the kit.

In 1974 the Peruvian Air Force purchased two 25Bs with a belly pod that contained an aerial survey camera.

Many Learjet 25 aircraft remain in regular use today, particularly in the United States, Mexico, and Canada.