Dyes are frequently used in industries such as textile, leather, paper and printing, to water sources causes harmful effects on the environment and human health. Therefore, it is crucial to effectively remove colored contaminants from water in order to protect the environment and public health, maintain biodiversity and preserve the esthetic aspects of water resources. In this study, wood chips obtained from Pinus brutia (PB) tree grown in many parts of the world were turned into biochar and then modified and used for the removal of malachite green, a cationic dye. For this purpose, biochar (PBB) was made by collecting PB wood and turning it into chips (PB). Later, PBB was modified to gain nano-magnetic properties. The structure of the obtained PBB and nM-PBB adsorbents was characterized by FT-IR. pH (2-9), temperature (25 & DEG;C-55 & DEG;C), time change (15 min-240 min), adsorbent amount change (0.05 g-0.45g) and MG concentration (25 mg/L-250 mg/L) were investigated in MG removal of PBB and nM-PBB. The process was found to be pseudo-second-order and spontaneous endothermic reaction. PBB and nM-PBB were found to be suitable for Langmuir isotherm in MG removal (q(max)=13.004 mg/g for PBB, q(max)=18.215 mg/g for nM-PBB). Novelty statementVarious adsorbents are used to remove different substances from water. The use of pinus brutia tree, which is a biochar product, in the removal of malachite green dyes from aqueous solutions has not been found in the literature. The findings revealed that Pinus brutia could be used to extract malachite green, a cationic dyestuff. Pinus brutia is a widely distributed, easy-to-access, low-cost species with many uses. Our study, in which Pinus brutian is used as an adsorbent, will contribute to the literature in this respect, and its use in the removal of different anionic and cationic dyes will be discussed in the future.