Background <p>Schizophrenia (SZ) is a severe chronic mental disorder characterized by pervasive impairments in cognition, emotion, perception, and behavior. We developed a novel group activity intervention aimed at improving cognitive function. The objective of this study was to investigate the effects of group activity therapy on cognitive functioning in patients with chronic schizophrenia.</p> Methods <p>In this 8-week, randomized, single-blind, controlled study, 100 schizophrenia patients with residual negative symptoms were randomly assigned to either the group activity or control group. Both groups continued their original antipsychotic treatments; however, the intervention group participated in an additional group activity program while the control group received standard rehabilitation programs. Assessment of psychotic symptoms and cognitive performance was conducted at baseline, week 4, and week 8 using the Positive and Negative Syndrome Scale (PANSS) and the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS).</p> Results <p>There were no significant changes in PANSS scores between the control and intervention groups at baseline, 4&#xa0;weeks, and 8&#xa0;weeks (p &gt; 0.05). After 8&#xa0;weeks of treatment, the intervention group exhibited significant improvements in Immediate Memory (IM), Visuospatial/Constructional (VC), Language, Attention, Delayed Memory (DM), and total RBANS scores compared to baseline (p &lt; 0.05). These cognitive gains were significantly greater than those observed in the control group (p &lt; 0.05).</p> Conclusions <p>Our findings indicate that group activity therapy can effectively improve cognitive impairment in schizophrenia patients with residual negative symptoms. Additionally, both age and duration of illness were found to negatively impact cognitive function recovery.</p>