Aeolis Mensae is a tableland feature in the northwest Aeolis quadrangle of Mars. Its location is centered at 2.9° south latitude and 219.6° west longitude, in the transition zone between the Martian highlands and lowlands. It is 820 kilometres (510 mi) long and was named after a classical albedo feature (Aeolis). The constituent mensae can be as long as 70 kilometres (43 mi) and as tall as 2 kilometres (1.2 mi). It is notable for being the origin of an abnormal concentration of methane detected by Curiosity in 2019, although its geology has attracted scientific attention since at least a decade before this event. Aeolis Mensae is also the first region in Mars where submarine cyclic steps, an erosion feature that gives evidence of an ancient ocean, were identified.

It was named in 1976, and examined in detail by Mars Express's HRSC camera in 2007. The Curiosity rover landed in the neighboring Gale Crater in 2012, and since then the area has received limited but continued attention from both ESA's HRSC and NASA's HiRISE cameras in orbit. In 2019, it was determined that Curiosity had detected methane originating from this region.

Due to the wealth of information coming from Curiosity about the local region, as well as the suspected presence of subsurface water, nitrates, aluminum, and iron, Aeolis Mensae has been considered as a candidate for a Martian habitat as early as 2016.

To Aeolis Mensae's south and west is Gale Crater, with the site of Curiosity rover's landing at Aeolis Pallus being between it and Mount Sharp (Aeolis Mons). Aeolis Mensae lies in the northwest corner of the Aeolis quadrangle, and thus the adjacent features lie in all four nearby quadrangles. Remaining in the Aeolis quadrangle, Aeolis Planum runs alongside northeastern edge of Aeolis Mensae. In the Tyrrhenum quadrangle, Robert Sharp Crater lies to Aeolis Mensae's west. Aeolis Mensae lies on the transition between Elysium Planitia (north, Elysium quadrangle) and Terra Cimmeria (south). The next geological figure along the transition zone, to Aeolis Mensae's northwest, is Nepenthes Menthae in the Amenthes quadrangle. This transition zone marks the boundary between the Martian highlands and lowlands, one of the defining features of the planet.

The linear escarpments mark the boundary between plains and plateau materials, and are parallel to fault lines in Elysium Planitia (such as Cerberus Fossae). These escarpments run northwest, although in the northeast direction there are also fractures which have split smaller mensae off of the main plateau.

A study from 2019 showed that the area of Aeolis Mensae is the most likely source of methane which was previously detected by Curiosity. While Martian methane levels are known to fluctuate seasonally, the spike of methane observed by Curiosity cannot be explained by this. The exact cause of the spike is unknown; possible hypotheses suggest either a geological or biological origin.

Aeolis Mensae is thought to have possessed an aquifer which was, along with the Elysium Planitia basin, a source of water for a lake in Gale Crater during the Amazonian period of Mars' development.

The surfaces of the mesas are between 3.5 and 3.7 billion years old. This is in contrast to the materials on the valley floors, which are at least 600 million years old. These ages were derived from crater-counting methods; the valley floors have been subject to much resurfacing and thus some craters may have been eroded. This would make the 600 million year estimate an underestimate; the valleys may have been carved earlier.