Nutritional stress induced by feed deprivation triggers coordinated metabolic and hematological adjustments in teleost fish. This study investigated the effects of short-term (9 days) and prolonged (18 days) starvation on liver glycogen reserves and key hematological parameters in striped catfish (Pangasius pangasius). Experimental fish subjected to 9 and 18 days of fasting exhibited a progressive, time-dependent depletion of hepatic glycogen reserves, confirmed via the Anthrone method, reflecting the primary reliance on glycogenolysis for energy homeostasis during initial energy deficits. Hematological profiling revealed significant alterations: red blood cell (RBC) counts, hemoglobin (Hb) concentrations, and hematocrit (HCT) values declined steadily, indicating reduced oxygen-carrying capacity and suppressed erythropoiesis under extended nutritional stress. Conversely, white blood cell (WBC) counts showed a marked elevation, pointing to a robust stress-induced immune response, while mean corpuscular volume (MCV) remained high, suggesting macrocytosis. Furthermore, platelet counts experienced a severe, precipitous drop of over 80%, highlighting compromised thrombopoiesis and blood-clotting potential. These findings demonstrate that while P. pangasius exhibits metabolic adaptations to conserve energy during food deprivation, extended starvation past 9 days severely compromises its hematological profile and metabolic stability.