The Mekong River is one of the world's major rivers. It is the world's 10th longest river and the 7th longest in Asia. (discharging of water annually). Its estimated length is , and it drains an area of . From the Tibetan Plateau it runs through China's Yunnan province, Burma, Thailand, Laos, Cambodia and Vietnam. All except China and Burma belong to the Mekong River Commission. A South- and Southeast Asian regional association, the Mekong-Ganga Cooperation, is named after this river and the Ganges river. The extreme seasonal variations in flow and the presence of rapids and waterfalls have made navigation extremely difficult.

Names

In English the river is called "the Mekong River", but in the Tai languages it is essentially the "Mae Nam Khong", where "Mae" translates as "Mother" and "Nam" translates as "Water". Many Northern Thai and Laos locals refer to it as the "River Khong", suggesting its origins and the subsequent formulation of "Mekong" literally meaning "Mother Khong". Such is the case with the Mae Nam Ping in Chiang Mai which is known as the "Ping River". The Tonle Sap in Cambodia is a similar example - where Tonle translates as "Great lake or river", making the Tonle Sap River an unnecessary repetition of what is in fact the "Sap River."

In Thai, โขง is a species of crocodile; some believe this is tone-shifted from คด or โค้ง , both adjectives to describe curves or meanders of a river or road.

Since the river flows through a number of countries, it has many different names in local languages.

• Tibetan: ?, ? and རྫ་ཆུ་1 rDza chu.
• Chinese: Riverhead: Lang: 加果空桑贡玛曲, Lang: 扎那曲 and Zā Qū, upper reaches: 澜沧江, Láncāng Jiāng ("Turbulent River", "Láncāng" is also same to Lan Xang in ChineseThe Chinese name of Lan Xang is both Nanzhang and Láncāng), middle and lower reaches: Méigōng hé.
• Burmese: မဲခောင္‌မ္ရစ္ Mè‘kaung Myit.
• Thai: แม่น้ำโขง , แม่โขง .
• Laotian: ແມ່ນ້ຳຂອງ , ນ້ຳຂອງ .
• Khmer: មេគង្គ Mekongk, ទន្លេមេគង្គ Tonle Mekongk, ទន្លេធំ‎ Tonle Thom ("Great River“).
• Vietnamese: Sông Mê Kông, Sông Lớn ("Great River"), Sông Cửu Long ("Nine Dragons River").

Fauna

The Mekong basin is one of the richest areas of biodiversity in the world. More than 1200 species of fish have been identified and there could be possibly as many as 1700. Fishing is a very important part of the economic activities in the area and a vital source of protein in the local diet. Estimates indicate that some 120 fish species are commercially traded but most of the fishery is based on 10-20 species.