In order to improve the surface properties of E690 steel used for automobile plate, the surface was strengthened by nanosecond laser shock. The effects of nanosecond laser shock times on its hardness and fatigue properties were analyzed. The action mechanism of E690 steel subjected to high energy pulse laser was studied, which provided a reference value for improving the anti-fatigue performance of E690 steel aeronautical components. The results show that the surface hardness of E690 steel can be increased and the residual compressive stress can be formed by increasing the nanosecond laser shock times. After 3 times of nanosecond laser shock, the saturated plastic deformation is reached. With the increase of the stress intensity factor (SIF) amplitude, the crack growth rate of the specimens subjected to multiple shocks decreased significantly. With the increase of nanosecond laser shock times, the crack length decreases and the fatigue life is enhanced. During the impact process, the fatigue band width decreases with the increase of nanosecond laser shock times. nanosecond laser shock causes the residual compaction on the surface of the alloy and closes the crack.