The present study aimed at analysing factors influencing the development of children aged one to under six years in four provinces across Thailand. Two sub-districts or communities were selected from each province. The population covered in the present study were 193 children aged one to under three years and 251 children aged three to under six years, and their main caregivers. The data was collected from April to September 2000. Denver II test kit was used to test the child development and a questionnaire was used to collect family and child factors. The results of analysis using Logistic Regression found that risk factors for lower child development among children aged one to under three years were father’s education at the primary school level or lower (OR = 3.0, 95%CI = 1.14, 7.9) and not having good household environments (OR = 2.9, 95%CI = 1.28, 6.8). The risk factors for lower development among children aged three to under six years were father’s education at the primary school level or lower (OR = 3.57, 95% CI = 1.74, 7.32) and inappropriate child raising (OR = 2.72, 95%CI = 1.48, 4.99). Families with fathers having a low level of
education, inappropriate household environments or inappropriate child raising should receive assistance so that children can have appropriate development for their age level.

Keywords: Children aged one to under six years, Development, Famil