Biochar has shown outstanding features in adsorption process and was widely used for removing organic and inorganic contaminants presents in water. Opuntia ficus-indica (OFI) which thrive in arid and semi-arid zones around the world and specially in Arab region. in this context, OFI cladodes present an intriguing source for producing biochar with inherent adsorption properties. This study aimed to assess and optimize the pyrolysis conditions (pyrolysis temperature and heating duration) for the adsorptive removal of anionic methyl orange (MO) and cationic malachite green (MG) dyes, the results demonstrates that at 400 °C as pyrolysis temperature and heating duration of 15 min are adequate for the production of efficient biochar with low energy consumption. The characteristics of OFI biochar produces at optimal conditions were explored using Fourier transform infrared spectroscopy (FTIR) and point of zero charge (pHpzc). The effect of contact time, solution pH and adsorbent dose on the adsorption efficiency of MG and MO dye were investigated. Moreover, To thoroughly understand the adsorption process, the pseudo-first-order and pseudo-second-order kinetic models, in addition to Langmuir, Freundlich and Temkin isotherm models were fitted to the experimental data, the results shows that the pseudo-second-order and Langmuir model consistently fits with the experimental data, suggesting a chemisorption adsorption, homogeneous and monolayer adsorption process for both anionic and cationic dye with adsorption capacity of 738.31 and 811.78 mg/g for MG and MO, respectively. This work presents a sustainable and a promising approach for the valorization of abundant natural waste and the mitigation of dye pollution.