A cross-sectional analysis of the Cambodia Demographic Health Surveys from 2000, 2005 and 2010 was conducted to observe the national trends in infant and young child feeding practices. The results showed that rates of exclusive breastfeeding among infants aged 0-5.9 months have increased substantially since 2000, concurrent with an increase in the rates of early initiation of breastfeeding and a reduction in the giving of pre-lacteal feeds. However, the proportion of infants being fed with breast-milk substitutes (BMS) during 0-5.9 months doubled in 5 years (3.4% to 7.0%) from 2000 to 2005, but then did not increase from 2005, likely due to extensive public health campaigns on exclusive breastfeeding. BMS use increased among children aged 6-23.9 months from 2000 to 2010 (4.8% to 9.3%). 26.1% of women delivering in a private clinic provided their child with breast-milk substitute at 0-5.9 months, which is five times more than women delivering in the public sector (5.1%), and the greatest increase in bottle use happened among the urban poor (5.8% to 21.7%). These findings are discussed with reference to the increased supply and marketing of BMS that is occurring in Cambodia.