Indoxyl sulfate (IS) is one of the most potent uraemic toxins involved in the progression of chronic kidney disease (CKD) through the induction of inflammation and oxidative stress. This study assessed the potential benefits of reducing IS concentrations through dialysis treatment to improve renal function, inflammation, and oxidative stress. A prospective, observational cohort study of 50 patients with CKD undergoing dialysis treatment was conducted. IS levels, inflammatory markers (IL-6 and hs-CRP), and oxidative status (Cu/Zn-SOD) were measured using immunoenzymatic methods, and the albumin ratio (HNA/HMA) was assessed using high-performance liquid chromatography. Blood samples were collected at baseline and, at 8 weeks and 16 weeks after treatment. At baseline, patients with CKD had elevated levels of IS, renal function indicators, inflammatory markers (IL-6 and CRP), and oxidative markers (Cu/Zn-SOD and albumin ratio HNA/HMA). Dialysis treatment reduced IS levels, and a correlation among IS, renal function, and SOD levels (P < 0.0001) at 8 and 16 weeks was observed. The reduction in IS levels was associated with improved inflammatory marker levels (CRP and IL-6; P < 0.0001) and a significant decrease in the HNA/HMA ratio (P <0.0001) at 8 and 16 weeks. These associations strengthened over time. The results of this study suggest that IS levels may be a therapeutic target for improving outcomes in patients with CKD by improving renal function, inflammation, and oxidative stress. More research is needed to understand how IS contributes to CKD complications.