The refractive index, refractive-index distribution, birefringence, and the attenuation of the plastic fiber prepared from the transparent PMMA prerod were measured in accordance with continuous heat drawing temperature($T_d$). The refractive indices were decreased with $T_d$ elevation but the refractive-index distribution from the center of fiber to periphery was higher at lower $T_d$. The steep decrease of gradient index was only at the periphery of higher $T_d$. Birefringence was observed only below $220^{circ}C$ and ranged $5{ imes}10^{-4}$ to $6{ imes}10^{-4}$. No birefringence was observed above $220^{circ}C$. An elevation of $T_d$ brought about a monotonous decrease in the attenuation of the fiber.