Because of the limitation that many semicrystalline polymers are not transparent, one cannot always study the network stress by optical methods. We suggest to use another tool in such a case. By measuring the azimuthal intensity distribution of the amorphous halo with wide-angle X-ray scattering experiments, one can determine the amorphous chain orientation induced in the strained network, which then results in the network stress. Experiments were carried out for a low-crystallinity polyethylene. They yield the relationships between the orientational order parameter associated with the halo, the birefringence produced by the amorphous chain parts, and the stress. The X-ray scattering results also show that the orientation of the amorphous segments under uniaxial drawing is comparable to the degree of orientation of the crystallites.