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.

大熊猫的历史可以追溯到大约800万年前，被誉为“活化石”的大熊猫化石最早于1915年发现于缅甸魔谷更新世洞穴堆积层中。我国大熊猫化石最早于20世纪20年代发现于重庆万县盐井沟石灰岩裂隙堆积层中。迄今为止，大熊猫发现地点已达几百处，分布范围覆盖了我国东部、中部乃至西北部的大部分省区，并延伸到东南亚的泰国、缅甸、老挝和越南等地。

从化石记录来看，更新世中期是大熊猫巴氏亚种空前繁盛的时期，分布范围覆盖我国长江、黄河和珠江三大流域，包括从北京附近周口店至两广以及附近的东南亚地区。与之形成对比的是，大熊猫现生种化石仅零星发现于广西、河南等地，未超出大熊猫巴氏亚种的分布范围，而现生大熊猫更是仅残存于我国秦岭、岷山、邛崃山、凉山、大相岭和小相岭等几大山系。

与大熊猫巴氏亚种相比，现今大熊猫的分布范围大大狭缩，这种狭缩可能自晚更新世时即已开始。考古发现新石器时代的广西来宾和仰韶文化时期的河南西南部山区（秦岭向东延伸部分）曾有大熊猫分布。商代“殷墟出土之兽类骨骼，动物群中有貘、竹鼠、象”，殷墟即今河南安阳，说明在商代河南曾有大熊猫分布。除此之外，西周时陕北黄土高原南边漆水一带，战国时汉水东北、湖北北部和河南西部一带也有大熊猫分布。近5000年来，从四川盆地周缘、湘西北和鄂西的武陵山北段，经鄂西巫山山地，到鄂西北的大巴山地以及西北山西及陕西关中、秦岭一带，甚至豫西南山地，可能都有大熊猫分布。除河南淅川附近外，其他许多地方大熊猫可能一直持续生存到18—19世纪。

目前主要分布于中国的四川、陕西南部、甘肃。中国特有种，野生数量不足1000 只，人工饲养下约100只。