The formation of carcinogenic by-products via the interaction between HA in water and chlorinated disinfectants underscores the crucial importance of studying HA removal methods. This study utilized abandoned corn stalks powder (CSP) as raw materials and employed an alkali-etherification method to prepare modified corn stalks powder (MCSP) to degrade humic acid (HA) in water, t. Single-factor experiments were conducted to investigate the effects of alkali concentration, alkalization time, etherification temperature, etherification time, and etherification concentration on the removal efficiency of HA. Response surface methodology was further used to optimize the preparation conditions of MCSP. The results revealed that the optimal parameters for the preparation of MCSP were: alkali concentration of 10%, alkalization time of 1.083 h, etherification temperature of 60 ℃, etherification time of 2.083 h, and etherification concentration of 50%. To further verify the effectiveness of MCSP, an experiment was conducted utilizing it for the removal of HA from water, and the results showed that the removal rate of HA gradually decreased with the increase of MCSP. This phenomenon was mainly because MCSP could neutralize the charge and increase the particle size in the HA system, thus achieving the goal of removing HA. Furthermore, it demonstrated the promising application prospects of MCSP in the treatment of HA pollutants in water.