Background: Physical plasma, the fourth state of matter formed through gas ionization, has shown promise in various clinical applications, including wound healing and antimicrobial therapy. Recently, Non-invasive physical plasma (NIPP) selectively disrupts tumor cell proliferation and metabolism without inducing cytoprotective stress responses, positioning it as a promising adjunct in oncological therapies, though its underlying mechanisms remain insufficiently understood. Methods: In this study, we investigated the effects of NIPP (Plasma Care device) on six tumor cell lines, ovarian (SKOV-3, OVCAR-3), prostate (LNCaP, PC-3), and breast (MCF-7, MDA-MB-231). Cell proliferation and migration were assessed using CASY analysis and scratch assays, while cytoskeletal integrity, heat shock protein (HSP) expression, and key metabolic indicators were evaluated through immunofluorescence, Western blotting, and biochemical assays. Results: NIPP treatment significantly inhibited tumor cell proliferation and migration, disrupted cytoskeletal organization, and altered metabolic activity in a time-dependent manner. These effects were associated with increased intracellular reactive oxygen species (ROS), decreased mitochondrial membrane potential (MMP), enhanced glycolysis, and elevated lactate production. Notably, despite cellular stress, neither HSP expression nor superoxide dismutase (SOD) activity showed significant changes, suggesting a lack of classical stress-response activation. Conclusions: Our findings indicate that NIPP selectively impairs tumor cell function by inducing oxidative stress and metabolic disruption, without triggering protective HSP-mediated resistance pathways commonly seen in radiotherapy and chemotherapy. These results highlight the therapeutic potential of NIPP, particularly via the Plasma Care device, as a novel anticancer strategy.