To study the effect of wetting-drying cycles on dynamic tensile strength of rock, dynamic indirect tension test of sandstone samples after 0, 1, 3, and 5 wetting-drying cycles was conducted. Tensile failure was observed by digital image correlation. The result shows that failure appears in the center of the samples initially, consistent with tensile strain field results obtained by digital image correlation. An empirical formula was derived to link loading rate and dynamic tensile strength of rock after wetting-drying cycles. As the loading rate increases, tensile strength increases significantly. Tensile strength reduces as the number of wetting-drying cycles increases. These results provide reference data for complex engineering problems such as those that occur in coal mining, tunneling and water conservancy.