The first census on Cambodia's people and population was carried out in 1998 finding that the Cambodia's population was 11.4 million and annual growth rate was 2.8%. The capital city of Phnom Penh was home to 1.2 million people and other populous areas included Sihanoukville, Siem Reap, Battambang, Takeo, Kompong Cham and Kompong Thom.

Ethnic groups in Cambodia included 90% Khmer,  5% Vietnamese, 1% Chinese and 4% others (the Muslim Cham and hilltribe groups).

According to the census, 85% of the population were involved in subsistence farming, some hill tribes practise slash-and-burn agriculture. The remainder 15% lived in urban areas.

Infant mortality in Cambodia was at 7.3% (73 per every 1.000 children born died). Malnutrition and mononuitritional diet caused the children stunted. Maternal mortality was at 6.4% (or 64 deaths per every 1,000 live births) due to poor sanitation and lack of facilities and due care. Life expectancy of the total population was 58.41 years  with that of the male was 55.71 years  and of the female was 61.23 years. The fertility rate was 3.51 children born/woman.