The majority of the global population lives in cities. In the developing world, a three-fold challenge of population growth, urbanization, and urban food insecurity is posing challenges for cities. Urban agriculture has received increasing attention as one strategy to help cope with this. Using the annual statistical data of the Ministry of Agriculture, Forestry, and Fisheries, this paper reported on trends in urban agriculture (rice, vegetables, cattle, swine, and poultry) in Phnom Penh, Cambodia since 1993. At least 125 square kilometers (~20%) of the municipal area of Phnom Penh is used in agriculture, with nearly 300,000 swine, cattle, and poultry. It is the sixth largest industry in the city and the most important secondary economic activity. Yield data for rice and vegetables are not significantly different between Phnom Penh and the Cambodian average. Cattle, swine, and poultry populations have been declining in Phnom Penh since 1993 but all increased in 2011. Between 1993 and 2011, vegetable production and area cultivated have decreased, whereas rice production has increased. To maximize the multifunctional benefits of urban agriculture in Phnom Penh, further research is needed to understand its importance at the household level and to ensure that it is being practiced effectively and sustainably.