Intra-body communication (IBC) is an alternative method for communication of devices in body area networks. The existing research is mainly focused on on-body (OB) channel modeling, transceiver design, and in vivo experiments. However, the difficulty arises in carrying out long-term in vivo experiments for investigating the human channel characteristics in OB or in-body (IB) IBC channels, since the repeatability of in vivo experiments shows inconsistency. In this paper, a multi-layer leg model with realistic shape was designed based on visible human data (VHD) images. Then, novel mixtures with the approximate conductivities of leg tissues were designed and used to fabricate leg phantoms, via several pairs of 3D-printed molds. Finally, the efficiency of the leg phantoms was validated by in vivo experiments through the high similarity of voltage gain versus distance characteristic of the OB channel. Both conditions featured the same trend, that is, they decreased first and then stabilized. The leg phantom was adopted to explore the channel characteristics of the IB channel. The results indicate that the voltage gain versus distance curve of the OB to IB channel was nearly reciprocal. In summary, the VHD-based leg phantom provides a reusable experiment platform for the IBC research, especially for the case of implantable channels.