The growth of aeroponic potato seedlings is sensitive to the ambient temperature as the roots are exposed to the air during cultivation. Effects of exogenous calcium treatment on physiological indexes of potato seedlings were studied in order to provide basis for improving the cold resistance by applying calcium reasonably in the low temperature production season. The results showed that the electrolyte leakage and MDA content in leaves of potato seedlings with calcium treatment were decreased, compared with the control, the activities of anti-oxidant enzymes (POD、CAT and SOD) in leaves were improved and the contents of osmotic adjustment substances (soluble sugar and soluble protein) in seedlings leaves were increased, however, the effect of calcium application on praline content in leaves was not obvious. Furthermore, calcium treatment could efficiently restrain the root activity drop of potato seedlings. The results above indicated that the calcium signaling was closely related to the physiological regulation of aeroponic potato seedlings in the low temperature condition, calcium application with appropriate concentration could improve the cold resistance of seedlings.