Abstract: Foliar application with stress-resistant and yield-increasing medium 10 (abbreviated as SR-10) to 3-leafed young seedlings of maize promoted the fresh weight, height, and net photosynthetic rate under double stress of drought and chilling (DSDC). SR-10 treatment also increased dark respiration, apparent quantum yield, decreased stomatal conductance, transpiration rate, and intercellular CO2 concentration. Furthermore, SR-10 treatment led to reduction in chlorophyll a fluorescence quantum yields, while increased photochemical efficiencies and potential activity of PSII. The data presented in this paper suggested that increased net photosynthetic rate induced by SR-10 under DSDC might be associated with induction of protective mechanism.