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Global structure of the M87 jet is examined by multi-frequency observations. Figure shows that distribution of the radius ($r$) of the jet as a function of the de-projected distance ($z$) from the core in units of $r_{\rm s}$: $z \propto r^{a}$. Three data points of mm/sub-mm VLBI cores (at 43, 86, and 230 GHz) are added as the most inner jet emissions at each frequency (Blandford & Konigl 1979). The solid line is the linear least-square for data points except three inner cores (VLBA at 43/86 GHz and EHT at 230 GHz), indicating the parabolic streamline with a power-law index $a$ of $1.73 \pm 0.05$. On the other hand, the dashed line indicates the conical streamline with $a$ of $0.96 \pm 0.1$. HST-1 is located around $5 \times 10^{5}\,r_{\rm s}$, where $r_{\rm s}$ is the Schwarzschild radius. The vertical dashed line indicates the Bondi radius, which is determined by the black hole mass, indicating the jet structural transition occurs beyond the share of the gravitational influence of the supermassive black hole.