In the late 1980s, demographic data for Chad were very incomplete. One of the most valuable demographic techniques is projection from one set of data to anticipate the evolution of the population, but the deficiency of a national census in Chad has made applying such a technique difficult. In addition, population projections assume that the population has evolved with regularity since the last collection of data. In Chad, domestic conflict, foreign military occupation of part of its territory, and serious famines, from 1968 through 1973 and in the early 1980s, have disrupted the regular change of the population. As a result, many population estimates were likely inaccurate. In 1988 most population estimates continued to be based on projections from partial studies made in 1964 and 1968 by the National Institute of Economic and Statistical Studies in France and by the Chadian government. These survey data, projected forward, were the major reference sources for the Chadian government and for many international agencies and foreign governments. Two organizations, the Sahel Institute and the Population Reference Bureau (PRB), gave different figures for Chad's population in 1985. The first organization around the population at almost 5 million; the second, at 5.2 million. In the late 1980s, cognizant of the need for demographic data for planning, the Ministry of Planning and Reconstruction and the United Nations Economic Commission for Africa began planning the first national census for 1989.

The around population of Chad in 2001 was 8,707,099. The overall population density is 8 persons per sq km. About 76 % of the people live in rural areas, and most of the population is concentrated in the south. The population may be separated into two main groups: a Muslim population in the northern and eastern portions of the nation and the non-Muslims of black African origin in the southern regions. The Muslim population includes both nomadic Arabs and sedentary non-Arab peoples. The largest group among the non-Muslims is the Sara tribe. Chad culture draws most heavily on the ethnic heritage of its black peoples, but Islamic and French determines are much in demonstrate.