Interfacial solar steam generation is an emerging strategy to improve the global freshwater supply. Herein, for the first time, a plausible alternative based on bone waste is presented for low-cost solar steam generation and seawater desalination. This is accomplished via the exploration of the appropriate carbonization conditions for the successful bone transformation into a porous carbonbased photothermal material. The carbonized bone (CB) not only is composed of inherent interlinked mesoporous microchannels for efficient water transportation but also displays broadband light absorption, photothermal conversion, and reduced vaporization enthalpy due to its special interactions with water. The as-prepared CB shows an apparent evaporation rate of 1.82 kg m−2 h−1 under one-sun illumination, attributed not only to its interaction with the sunlight but also to its performance in the dark field, and a solar-to-vapor conversion efficiency of 80%. Furthermore, CB desalinates water with an efficiency of 99.99%. Such performance combined with its wide availability, facile fabrication, and stability makes this biowaste-based porous material a promising system for the production of freshwater. In this way, a valuable alternative for the valorization of bone-based food-waste is offered, paving the way to new routes for the management of such, continuously growing, food-waste products.