We present a case of puffer fish poisoning that developed marked changes in hemodynamic status. A 42-year-old man recognized numbness in his fingers and lips 3 hours after tasting pieces of puffer fish liver, and was admitted to our emergency center with dyspnea. Since spontaneous breathing weakened after admission, mechanical ventilation was started. One hour after admission, his blood pressure gradually decreased to 60mmHg with a pulse rate of 60/min. Rapid infusion and dopamin administration successfully elevated and stabilized his hemodynamics. However, his blood pressure increased to 235mmHg accompanied with remarkable sweating 6 hours later. Although dopamin was discontinued, his blood pressure re-elevated and required nicardipine to decrease and stabilize it. Thirty-two hours after admission, spontaneous breathing resumed and he was extubated. Analyses of his hemodynamics using a Swan-Ganz catheter revealed that the cardiac index decreased to 1.9l/min/m² with a normal systemic vascular resistance (SVRI 1, 780dynes/sec/cm^-5/m²) when his blood pressure decreased. On the other hand, elevation of blood pressure was accompanied with increases of both cardiac index and vascular resistance. The extreme changes in hemodynamics in this case were thought to be caused by the time course of impairment and recovery of the peripheral sympathetic nerves induced by the tetrodotoxin in puffer fish.