The effect of simple shear flow on molten polyethylene is studied using in situ time-resolving wide-angle X-ray scattering procedures. A small degree of global molecular orientation is observed under shear flow which is linearly related to the logarithm of the shear rate. The system rapidly relaxes to an isotropic state upon cessation of shear flow. A sharp temperature drop coupled with the cessation of shear flow leads to the development of crystallinity, and it is found that the shear flow prior to crystallization has a strong effect on the degree of orientation in the recrystallized state. In fact, above a critical prior shear rate, the recrystallized state changes from globally isotropic to globally anisotropic.