Generalized pustular psoriasis (GPP) is a rare form of psoriasis characterized by the presence of variable numbers of sterile pustules appearing in erythematous and scaly lesions, which are associated with moderate to severe constitutional symptoms. It can be life-threatening especially in the elderly; therefore, medical care must be performed in rapid succession of treatment especially in refractory cases. We have performed granulocyte and monocyte adsorption apheresis (GCAP) on three GPP cases associated with several systemic and laboratory findings. As a result, the edema, erythema and numbers of sterile pustules on the skin lesions were reduced dramatically in all three patients after the first sessions of GCAP therapy. The sizes of the psoriatic lesions were reduced in all three patients following a weekly GCAP treatment for 5 consecutive weeks. Psoriasis area and severity index on discharge had improved in all three patients. No serious adverse effects were observed for up to at least 8 months after treatment. We therefore considered GCAP as one effective alternative to currently existing therapies, especially for recalcitrant cases of GPP.