The displacement field generated by aftershocks in Landers earthquake fault zone and its adjacent areas is calculated in this study. The result is compared with the displacement field of the main shock calculated by co-seismic slip model of Wald and Heaton (1994). The result shows that the direction of displacement generated by aftershocks in Landers seismic fault plane and its adjacent areas is consistent with that generated by main shock. The rupture of aftershock is generally inherited from main shock. The displacement generated by aftershocks is up to an order of centimeter and can be measured by GPS sites nearby. So when we use geodetic data measured after earthquake to study the geophysical problems such as crustal viscosity structure, afterslip distribution, etc., only the displacement field generated by aftershocks considered, can uncertainty be reduced to minimum and realistic result be obtained.