Real-time and in-situ small-angle X-ray scattering (SAXS) studies were conducted on polystyrene-block-poly(ethylene-alt-propylene) copolymer films having alternating lamellar microdomains. SAXS was detected with a 2D detector from the film specimens subjected to a large-amplitude oscillatory shear deformation with a sawtooth type strain gamma (-0.5 less-than-or-equal-to gamma less-than-or-equal-to 0.5) at frequency f = 0.0149 or 1 Hz and at temperature T = 105 or 130-degrees-C. The specimens initially had a uniaxial orientation with the lamellar normal 1 preferentially oriented parallel to the film normal (OZ axis). The shear deformation at low temperature and low frequency (f = 0.0149 Hz, T = 105-degrees-C) or that at high temperature and high frequency (f = 1 Hz, T = 130-degrees-C), with the displacement vector parallel to the OY axis and the shear gradient axis parallel to the OZ axis, gave a biaxial orientation with 1 preferentially oriented along either the OZ or OY axis, the former being dominant to the latter. On the other hand, the shear deformation at high temperature and low frequency (f = 0.0149 Hz, T = 130-degrees-C) gave an improved uniaxial orientation of 1 with respect to the OZ axis. A preferred orientation of 1 along the OX axis, the neutral axis, was not detected in any case. The two deformations which gave the biaxial orientation involved about the same shear stress level, but this stress level was much higher than that involved in the deformation giving rise to the improved uniaxial orientation.