In this study, we tried to find quantitative scaling properties of the Parkinson s disease (PD) s center of pressure (COP) trajectory by comparison of the COP parameters between healthy and PD. The experimental group was composed of 13 people with Parkinson s disease (68.77 ± 4.94 yrsl, and the control group was composed of age-matched 13 healthy people. Subjects were asked to stand quietly on a pressure mat with four different conditions - 1) eye open, 2) eye closed, 3) eye open on a balance pad, and 4) eye closed on a balance pad. The movements of the COP were recorded and stored in a computer when a subject performed those four different tasks on the sensor. Sway range of displacement in anterior-posterior (Rx) and medio-lateral (Ry) directions, a total length of trajectory (L), and sway area (A) as well as scaling exponents (α) from DFA were calculated from measured data. All temporal behaviors of the COP (Rx, Ry, L, and A) in condition 1, 2, 3 showed significant differences between healthy and PD groups. In condition 4 (eye closed on a balance pad) , the scaling exponent alpha of the Ry showed significant differences between healthy and PD groups. It is hard to distinguish the cause of balance impairment whether it was due to the aging or PD. However, the DFA scaling exponent is considered as useful quantitative variable that tells that the Parkinsonian person has decreased function of proprioception integration.