Total population was around in 1994 at 17,268,000, making Kazakstan the fourth most populous former Soviet republic. As of 1990, 57 % of the nation's residents lived in cities. Because much of the land is too dry to be more than marginally habitable, overall population density is a very low 6.2 persons per square kilometer. Large portions of the republic, particularly in the south and west, have a population density of less than one person per square kilometer. In 1989 some 1.4 million Kazaks lived outside Kazakstan, nearly all in the Russian and Uzbek republics. At that time, an around 1 million Kazaks lived in China, and a sizeable but uncounted Kazak population resided in Mongolia.

The Kazaks are a nominally Muslim people who speak a Turkic language of the Northwest or Kipchak (Qipchaq) group. Fewer than one-fifth of the more than eight million ethnic Kazaks live outside Kazakstan, mainly in Uzbekistan and Russia. During the 19th century about 400,000 Russians flooded into Kazakstan, and these were supplemented by about 1,000,000 Slavs, Germans, Jews, and others who immigrated to the region during the first third of the 20th century. Another large influx of Slavs occurred from 1954 to 1956 as a result of the Virgin and Idle Lands project, initiated by the Soviet premier Nikita Khrushchev, himself a Slav. This project drew thousands of Russians and Ukrainians into the valuable agricultural lands of northern Kazakstan. By 1989, Kazaks slightly outnumbered Russians.