Schizophrenia is a severe psychiatric disorder characterized by positive symptoms (e.g., hallucinations), negative symptoms (e.g., social withdrawal), and cognitive impairments. Among these, cognitive impairment is a core feature that severely compromises patients’ social functioning and long-term prognosis. Antipsychotics, the first-line treatment for schizophrenia, are generally effective in managing positive symptoms. However, their efficacy in alleviating negative symptoms and cognitive deficits remains limited. Moreover, long-term use may lead to metabolic syndrome and extrapyramidal side effects. Consequently, non-pharmacological interventions have garnered increasing attention as alternative or adjunctive strategies for cognitive remediation in schizophrenia. In recent years, techniques grounded in neuroplasticity theory have advanced rapidly. These interventions aim to alleviate cognitive impairments by modulating neural circuits (e.g., enhancing prefrontal-hippocampal connectivity) and synaptic plasticity (e.g., modulating the BDNF/TrkB pathway) from multiple dimensions. Such approaches not only enhance cognitive function but also reduce medication-related adverse effects and improve treatment compliance. This article comprehensively reviews the clinical evidence and recent technological advances in non-pharmacological interventions targeting cognitive impairments in schizophrenia. The interventions discussed include cognitive remediation therapy (CRT), repetitive transcranial magnetic stimulation (rTMS), transcranial direct current stimulation (tDCS), electro-acupuncture (EA), aerobic exercise (AE), and light therapy (LT). CRT, the most extensively studied and evidence-based intervention, uses structured cognitive training tasks to enhance neuroplasticity and has consistently demonstrated efficacy in improving executive function and social cognition. Both rTMS and tDCS are non-invasive brain stimulation techniques that modulate cortical excitability and neural network connectivity. While rTMS has shown promise in improving working memory and attention—particularly in patients with prominent negative symptoms—its clinical efficacy remains inconsistent, likely due to variability in stimulation parameters and patient heterogeneity. In contrast, tDCS has demonstrated encouraging effects on working memory and attention with a relatively rapid onset, although optimal stimulation protocols have yet to be standardized. EA, which combines traditional acupuncture with electrical stimulation, has been shown to improve memory function, possibly through upregulation of brain-derived neurotrophic factor (BDNF) and enhanced cerebral blood flow. It may be especially useful in treatment-resistant cases. AE is a low-cost and widely accessible intervention that promotes hippocampal neuroplasticity and BDNF expression, thereby improving memory and attention. It is recommended as a foundational adjunctive therapy, particularly for patients with chronic schizophrenia. LT, although still experimental, has yielded promising results in animal models by modulating neuroinflammation and enhancing neurogenesis via the BDNF/CREB signaling pathway. However, clinical evidence remains limited, necessitating further large-scale trials to validate its efficacy and safety. In addition to reviewing individual interventions, this article highlights the potential of combination strategies—such as CRT combined with AE or rTMS—to produce synergistic cognitive benefits. Future directions include the development of personalized treatment protocols, early intervention during neurodevelopmental windows (e.g., adolescence), and the integration of biomarkers and neuroimaging to guide therapeutic decisions. This synthesis aims to provide clinicians and researchers with a comprehensive framework for advancing non-pharmacological cognitive rehabilitation in schizophrenia.