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The anisotropy of solar wind turbulence is a critical issue in understandingthe physics of energy transfer between scales and energy conversion betweenfields and particles in the heliosphere. Using the measurement of \emph{ParkerSolar Probe} (\emph{PSP}), we present an observation of the anisotropy atkinetic scales in the slow, Alfv\'enic, solar wind in the inner heliosphere.\textbf{The magnetic compressibility behaves as expected for kinetic Alfv\'enicturbulence below the ion scale.} A steepened transition range is found betweenthe inertial and kinetic ranges in all directions with respect to the localbackground magnetic field direction. The anisotropy of $k_\perp \ggk_\parallel$ is found evident in both transition and kinetic ranges, with thepower anisotropy $P_\perp/P_\parallel > 10$ in the kinetic range leading overthat in the transition range and being stronger than that at 1 au. The spectralindex varies from $\alpha_{t\parallel}=-5.7\pm 1.0$ to $\alpha_{t\perp}=-3.7\pm0.3$ in the transition range and $\alpha_{k\parallel}=-3.12\pm 0.22$ to$\alpha_{k\perp}=-2.57\pm 0.09$ in the kinetic range. The correspondingwavevector anisotropy has the scaling of $k_\parallel \sim k_\perp^{0.71\pm0.17}$ in the transition range, and changes to $k_\parallel \simk_\perp^{0.38\pm 0.09}$ in the kinetic range, consistent with the kineticAlfv\'enic turbulence at sub-ion scales.

Anisotropy of Solar-Wind Turbulence in the Inner Heliosphere at Kinetic Scales: PSP Observations