The effects of drawing temperature and annealing temperature on the physical properties and structure of poly(trimethylene terephthalate)(PTT) fibers were investigated by measuring drawability, WAXD, DSC, density birefringence, dynamic viscoelasticity, and tensile testing. Undrawn and partially oriented PTT yarn had different optimum drawing temperatures because of their drawing behavior. As the annealing temperature increased, the intensity of maximum tan $delta$ decreased and the temperature of maximum tan$delta$ shifted to a higher temperature, but shifted to a lower temperature when the annealing temperature exceeded 130 $^{circ}C$. As the annealing temperature increased, the crystallinity increased and mechanical properties was improved. The annealing was more effective in controlling the structure of PTT fibers than the drawing.