Polyethylene terephthalate (PET) fibers spun at the take-up velocity of 5,800 m/min was annealed at various temperature, and the changes of structure and dyeing properties of the fiber on annealing were studied. Crystallinity increased and orientation decreased significantly with an increase in annealing temperature over 180 $^{circ}C$. Dyeing properties of the fibers were measured from the dye adsorption curves and analyzed with the dyeing transition temperature ( $T_{d}$), dyeing rate constant (k), and dye-uptake. Dyeing transition temperature showed a maximum and dye-uptake showed a minimum around 180 $^{circ}C$ for the annealed HOY. The dependency of $T_{d}$ and k on annelealing temperature was well related with the change of amorphous state represented by $X_{v/}$ $V_{c9}$, where $X_{v}$ is volume fraction crystallinity and $V_{c}$ is mean crystal volume. The change of dye-uptake was explained with the change in amorphous volume caused by annealing.aling.aling.