火星地质，包含火星的组成、结构、物理性质、地质史等等。

火星全球勘测者上的热辐射光谱仪（TES）所测，以玄武岩和安山岩来说，北方低原和南方高地安山岩较多，而南方高地近赤道的部份区域则玄武岩较多，但是有部分地表由于被沙尘覆盖而未知下方岩性。

各探测器分析着陆地点的土壤成分：

The geology of Mars is the scientific study of the surface, crust, and interior of the planet Mars. It emphasizes the composition, structure, history, and physical processes that shape the planet. It is analogous to the field of terrestrial geology. In planetary science, the term geology is used in its broadest sense to mean the study of the solid parts of planets and moons. The term incorporates aspects of geophysics, geochemistry, mineralogy, geodesy, and cartography. A neologism, areology, from the Greek word Arēs (Mars), sometimes appears as a synonym for Mars's geology in the popular media and works of science fiction (e.g. Kim Stanley Robinson’s Mars trilogy), but the term is rarely, if ever, used by professional geologists and planetary scientists.