Double burden of malnutrition (DBMN), the coexistence of under- and overnutrition in the same population, is an emerging public health concern in developing countries, including Thailand. This paper aims to review the maternal and child nutrition situation and trends as the country moved from a low-income to a middle-income country, using data from large scale national surveys. Protein-energy malnutrition and micronutrient deficiencies predominantly affected mothers and children prior to the 1980s. The situation greatly improved during the 1980s- 1990s, with the implementation of multi-sectoral policies and programs focusing on poverty alleviation and primary health care. Economic development, improved access to health services and effective community-based nutrition programs contributed to these positive trends. However, the prevalence of low birth weight remained at 8- 10%, while stunting and underweight declined to about 10% by the 1990s, with small change thereafter. The prevalence of anemia among pregnant women and children decreased by half and vitamin A deficiency is no longer a public health problem. Iodine deficiency, especially during pregnancy is still a major concern. As the country progressed in terms of economic and social development, overnutrition among women and children affected all socio-economic levels. Changes in lifestyles, food access and eating patterns are observed both in urban and rural areas. Although efforts have been made to address these challenges, harmonized policy and strategic programs that address DBMN in the complex social and economic environment are urgently needed. Early life undernutrition should be considered along with measures to address obesity and chronic diseases in children.