Lithium (Li) metal is the ultimate anode material for Li batteries because of its highest capacity among all candidates. Recent research has focused on stable interphase and host materials to address its low stability and reversibility. Here, we discover that tortuosity is a critical parameter affecting the morphology and electrochemical performances of hosted Li anodes. In three types of hosts—vertically aligned, horizontally aligned, and random reduced graphene oxide (rGO) electrodes with tortuosities of 1.25, 4.46, and 1.76, respectively—we show that high electrode tortuosity causes locally higher current density on the top surface of electrodes, resulting in thick Li deposition on the surface and degraded cycling performance. Low electrode tortuosity in the vertically aligned rGO host enables homogeneous Li transport and uniform Li deposition across the host, realizing greatly improved cycling stability. Using this principle of low tortuosity, the designed electrode shows through-electrode uniform morphology with anodic Coulombic efficiency of ∼99.1% under high current and capacity cycling conditions. Display omitted •Controllable alignment and tortuosity in Li-metal host•Low tortuosity mitigates locally enhanced concentration gradient and current density•Suppress uneven Li dendrite overgrowth on top surface by decreasing host tortuosity•Strong correlation between host tortuosity and reversibility of hosted Li-metal anode Host electrodes, such as three-dimensional (3D) porous carbon matrices, can accommodate the relative infinite volume change and decrease the local current density for mitigating dendritic growth and reversibility issues in a Li-metal anode. However, a preferential Li accumulation on the upper surface of the host is commonly observed during cycling, which has not been rationalized or addressed. Here, we show that the host tortuosity, as a complexity of the microstructure inside the 3D host, is responsible for this uneven Li distribution. In comparisons between rGO hosts with different tortuosities, the locally enhanced current density and concentration gradient showed a strong correlation with high host tortuosity, leading to top-surface accumulation of Li dendrites and a blocked ion-transport pathway. When the host tortuosity was reduced from 4.46 to 1.25, rGO hosts exhibited a doubled cycle life in full cells with high uniformity within the anode, suggesting the importance of this tortuosity parameter for stable Li-metal batteries. A strong correlation between host tortuosity and cycling reversibility of a hosted Li-metal anode is revealed for the first time. High tortuosity leads to preferential top-surface Li deposition based on locally enhanced current density and concentration gradient. This top-surface accumulated Li blocks inward ion transport and invalidates the internal electrode, further aggravating the uneven current distribution and non-uniform plating and stripping. Decreased electrode tortuosity can significantly improve the anodic Coulombic efficiency, uniformity of Li-metal stripping and plating, and cycling stability of the rGO host.