The fossil record of the giant panda is incomplete. Some intermediate stages have been suggested. A small bear like animal, Agriarctos, that lived in the mid Miocene (about 3 million years ago) is an ancestor of the giant panda. The fossils of the present day giant panda can be found from the Early Pleistocene. There may have been as many as 4 species of Ailuropoda. Fossils of Ailuropoda microta, one species, was found to have lived in the early Pleistocene. They were about 1/2 the size of present day pandas. Fossils of Ailuropoda melanoleuca, the present day giant panda, appear in the mid Pleistocene. The distribution of giant pandas was much more extensive in the Pleistocene. Fossils have been found in present day Burma and Vietnam.

The giant panda has been declining for thousands of years due to hunting by humans and climatic changes. Its populations originally extended throughout most of southern and eastern China, northern Myanmar, and northern Vietnam. By 1900, it occurred only in the Qinling Mountains and along the edge of the Tibetan plateau. Soon after 1900, the expansion of agriculture upstream along principal river valleys separated this distribution into separate regions in six mountain ranges. Currently, the giant pandas distribute in six mountain ranges including Qinling, Minshan, Qionglai, Liangshan, Daxiangling and Xiaoxiangling in Shaanxi, Gansu and Sichuan provinces. The distribution of Qinling giant pandas have isolated from that of Sichuan giant pandas since 12 thousand years ago.

Giant panda is rare and endangered species endemic to China. The low rates of reproductive success and infectious disease resistance have severely hampered the development of captive and wild populations of the giant panda.

The giant panda weighs 70 - 125 kg (154 - 275 lb). It occupies montane forests with dense stands of bamboo at altitudes of 2700 - 3900 m (8850 - 12,800'). The panda does not hibernate but descends to lower elevations in the winter (usually not lower than 800 m (2600') to reach warmer temperatures. It does not make a permanent den but takes shelter in hollow trees, rock crevices and caves. Although it is predominantly terrestrial, the giant panda can climb trees well. Activity patterns are largely crepuscular and nocturnal. Ten to twelve hours a day are spent feeding, mainly on bamboo (which comprises 99 % of its diet). Giant pandas are usually solitary, except during the mating season.

Now, most pandas are distributed in Sichuan, south Shanxi and Gansu. The amount of wild pandas is less than 1000 and the artificial breeding is about 100.

大熊貓的歷史可以追溯到大約800萬年前，被譽為“活化石”的大熊貓化石最早於1915年在緬甸魔谷更新世洞穴堆積層中發現。我國大熊貓化石最早於20世紀20年代在重慶萬縣鹽井溝石灰岩裂隙堆積層中發現。迄今為止，大熊貓發現地點已達幾百處，分佈範圍涵蓋了我國東部、中部乃至西北部的大部分省區，並延伸到東南亞的泰國、緬甸、老撾和越南等地。

從化石記錄來看，更新世中期是大熊貓巴氏亞種空前繁盛的時期，分佈範圍涵蓋我國長江、黃河和珠江三大流域，包括從北京附近周口店至兩廣以及附近的東南亞地區。與之形成對比的是，大熊貓現生種化石僅零星發現於廣西、河南等地，未超出大熊貓巴氏亞種的分佈範圍，而現生大熊貓更是僅殘存於我國秦嶺、岷山、邛崍山、涼山、大相嶺和小相嶺等幾大山系。

與大熊貓巴氏亞種相比，現今大熊貓的分佈範圍大大縮小，這種縮小可能自晚更新世時即已開始。考古發現新石器時代的廣西來賓和仰韶文化時期的河南西南部山區（秦嶺向東延伸部分）曾有大熊貓分佈。商代“殷墟出土之獸類骨骼，動物群中有貘、竹鼠、象”，殷墟即今河南安陽，說明在商代河南曾有大熊貓分佈。除此之外，西周時陝北黃土高原南邊漆水一帶，戰國時漢水東北、湖北北部和河南西部一帶也有大熊貓分佈。近5000年來，從四川盆地周緣、湘西北和鄂西的武陵山北段，經鄂西巫山山地，到鄂西北的大巴山地以及西北山西及陝西關中、秦嶺一帶，甚至豫西南山地，可能都有大熊貓分佈。除河南淅川附近外，其他許多地方大熊貓可能一直持續生存到18、19世紀。

目前主要分佈於中國的四川、陝西南部、甘肅。中國特有種，野生數量不到1000 隻，人工飼養約100隻。