The influence of internal curing technology by super absorbent polymer(SAP) on the properties ( e.g. autogenous shrinkage,drying shrinkage and water loss rate) of C40 and C60 concrete with natural volcanic ash were analyzed. The results show that internal curing with SAP can significantly reduce the autogenous shrinkage of C40 and C60 pozzolanic concrete, improve the crack resistance of pozzolanic concrete, and the fitting relationship between autogenous shrinkage reduction rate and internal curing water binder ratio is obtained. Internal curing with SAP increases the drying shrinkage and water loss rate of pozzolanic concrete. Increase in amplitude is enlarged as the quantity of internal curing water increases. Based on the fitting relationship between water loss rate and dry shrinkage of pozzolanic concrete in dry environment, the critical water loss rate of pozzolanic concrete during drying shrinkage is obtained. Although internal curing increases the drying shrinkage of pozzolanic concrete, the shrinkage performance is superior to that of control concrete.