Insufficient academic attention has been paid to household water conservation behavior in arid and semi-arid areas of developing countries. Based on a questionnaire survey, this study analyzed factors influencing the water conservation behavior of urban residents in Zhangye City in China. Of the two variables addressed in the theory of reasoned action, attitudes toward water conservation had no obvious influence on water conservation behavior, whereas subjective norms did have an influence. Furthermore, general environmental concerns had no direct, significant influence on water conservation behavior. It has been argued that environmental motivational factors have a limited influence on water conservation behavior. The theory of reasoned action may not sufficiently explain domestic water conservation behavior in the study area, where the economy remains underdeveloped. Three contextual factors, beliefs regarding local water resources, incremental water conservation information and attitudes toward frugality, were significantly correlated with water conservation behavior.