Rotation Curve of the Milky Way and the Dark Matter Density

We review the current status of the study of rotation curve (RC) of the Milky Way, and present a unified RC from the Galactic Center to the galacto-centric distance of about 100 kpc. The RC is used to directly calculate the distribution of the surface mass density (SMD). We then propose a method to derive the distribution of dark matter (DM) density in the in the Milky Way using the SMD distribution. The best-fit dark halo profile yielded a local DM density of rho(circle dot) = 0.36 +/- 0.02 GeV cm(-3). We also review the estimations of the local DM density in the last decade, and show that the value is converging to a value at rho(circle dot) = 0.39 +/- 0.09 GeV cm(-3).