AIM: To examine the selective cytotoxic effects of Electro-Capacitive Cancer Therapy (ECCT) on human glioblastoma (GBM) cell lines (U87-MG and T98-G) and to evaluate its impact on normal epithelial cells. MATERIAL and METHODS: U87-MG and T98-G glioblastoma cells, along with Beas-2B normal epithelial cells, were exposed to ECCT at 100 kHz frequency and 20 V for 24 hours. Cell viability was determined using the MTT assay, while morphological changes were assessed through phase-contrast microscopy. Statistical analyses were conducted using one-way ANOVA and Student’s t-test, with statistical significance defined as p < 0.05. RESULTS: ECCT exposure caused a time-dependent reduction in the viability of both GBM cell lines. U87-MG cells showed significant inhibition at all exposure durations, whereas T98-G cells exhibited a marked decrease only after 24 hours (p < 0.0001). In contrast, Beas-2B cells maintained their morphology and viability, suggesting that ECCT selectively targets malignant cells while sparing normal epithelial cells. CONCLUSION: ECCT significantly inhibits glioblastoma cell proliferation without adversely affecting normal cells, highlighting its promise as a non-invasive adjunctive treatment option for GBM. Further preclinical and clinical studies are warranted to clarify its underlying mechanisms, optimize exposure parameters, and determine its potential integration into multimodal glioblastoma therapy.