The coconut shell-based activated charcoal was decorated by three different electronegativities of surfactants (CTAB, SDS, and Triton X-100) through the impregnation method, and the decorated activated charcoal adsorbents were used for the removal of PAHs from peanut oil, respectively. The influence of surfactant decoration on the adsorption and detoxification effect of coconut shell-based activated charcoal was discussed. The thermodynamic and kinetic behaviors of PAHs adsorption on the surfactant-modified activated charcoal were investigated, and the adsorption mechanism was analyzed in-depth. Notably, the prepared modified coconut shell activated charcoal could not only remove more than 90% of PAHs from the peanut oil but also keep the cytotoxicity of the treated peanut oil low. Meanwhile, the detoxification procedure has little effect on the nutritional quality and flavor of the peanut oil. The results of this fundamental study demonstrate that the low-cost surfactant-modified coconut shell-based activated charcoal was effective and feasible.