Amorphous films of poly(ethylene naphthalene-2,6-dicarboxylate) were drawn isothermally up to desired draw ratios at 130, 140, 150 and 160 degrees C mainly to study structure formation during uniaxial drawing by wide-angle X-ray diffraction (WAXD). The results were analysed in comparison with stress-strain curves in order to find the draw ratio associated with the onset of crystallization at the above-mentioned temperatures. To obtain further detailed information, birefringence and density were measured for the films drawn at 150 degrees C to elucidate the relationship between the degree of chain orientation and the crystallinity. A series of results was discussed in relation to previously reported interesting phenomena of the time-resolved two-dimensional WAXD patterns recorded using the imaging plate system (Polymer 1995, 36, 291).