The aim of this research is to investigate and identify the absorption capacity of activated carbon derived from a rubber seed shell (RSS). An RSS was prepared through the conduction of a chemical activation process primarily using potassium hydroxide at a ratio of 1:1 followed by carbonisation at 400°C with N2 under a steady flow rate of 1 ml min–1 for 3 h. The produced RSS activated carbon (RSSAC) which was characterised using Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopyenergy dispersive X-ray (SEM-EDX) spectroscopy, Brunauer-Emmet-Teller (BET) analysis and thermogravimetric analysis (TGA). The SEM image obtained revealed the presence of a highly porous RSSAC surface, with an average pore diameter of 3.35 nm, indicating a mesoporous structure. EDX analysis depicted that C and K were major elements found in RSSAC with a compound percentage of 99.73% and 0.27%, respectively. Batch adsorption studies were conducted to investigate the adsorption properties of RSSAC towards the removal of methylene blue (MB) dye. The optimum dosage of RSSAC was determined to be 5.0 g per 100 ml. Effect of contact time revealed that the highest percentage removal of MB (99.62%) by RSSAC was obtained at a concentration of 100 mg l–1 during a time period of 1 h. In comparison, the effect of pH study affirmed that RSSAC achieved an average removal of 99% of MB in both acidic and basic media at 100 mg l–1. Kinetic studies revealed that the adsorption process abides by the pseudosecond- order kinetic model. Based on the findings by utilising multiple approaches as mentioned, it can be proposed that RSSAC is a viable alternative to act as a green alternative adsorbent.