The effect of heating modes in drawing process on the structure and properties of PET fibers was investigated．Sample B was prepared by drawing amorphous as-spun PET filaments under laser radiation．A CO2 laser (γ=10.6 μm

30 W) was used for this purpose

and the diameter of its radiation area was about 3 mm．The feeding speed of the filaments was 50 m／min

and the draw ratio was 5.0．Sample A was prepared under the same conditions except the heating mode

the filaments were heated by hot rolls．Some difference in structure and mechanical properties were found for the two samples．Sample B exhibited high tenacity (0.8 GPa)

elongation (9.2％) and toughness (O.047 GPa)．The latter was about 1.8 times as high as that of sample A．Both of the samples were obviously oriented．WAXD and density measurements showed the crystallinity and the crystallite size of sample B were larger than those of the sample A．