The main objective of this research was to optimize the biochar production process using olive pomace waste through a comprehensive 3-factor design of experiments with a Full Factorial Design model. The study focused on examining the individual effects of three crucial factors: biomass size, reactor temperature, and pyrolysis reaction time on biochar yield, employing a 1st degree polynomial mathematical model. The results highlighted the significant influence of these factors on the pyrolysis process. Moreover, the elaborated biochars underwent extensive physicochemical analyses, including Scanning Electron Microscope coupled with Energy Dispersive X-Ray (SEM/EDX) and X-ray diffraction (XRD), and porosity parameters were determined using the Brunauer–Emmett–Teller method (BET). Stressing the importance of precise factor control, the research emphasized achieving higher biochar yields and promoting sustainability in production. Overall, this study provides valuable insights into biochar production, offering valuable guidance for future research to enhance its environmental applications.