A sustainable food consumption and production system is at the center of the global sustainability initiative. With the world's largest population and rapidly growing environmental concerns, it is urgent for China to develop effective ways to motivate sustainable food consumption and production. Understanding consumer perception and preference of sustainable food provides critical information for Chinese policy makers to identify barriers and develop rules and policies to reach this goal. Our paper shows that most Chinese consumers do not clearly understand the meaning of sustainability, and lack knowledge about sustainable food production. The premium that consumers are willing to pay for sustainable milk is about 40%. Consumers who do not perceive the linkage between sustainable production and food quality have a significant lower willingness to pay for sustainable milk. Interestingly, people with children are more willing to pay for sustainable milk, suggesting a potential over-generation concern about sustainable development.