Clinical experiences of endotoxin removal using polymyxin B immobilized fiber column (PMX) in three septic shock patients are reported. The patients were referred to our hospital with complaints of high fever and severe pain during urination. Physical examination and laboratory data revealed severe hypotension, tachycardia, and pyuria. Diagnoses of septic shock due to urosepsis were made. After antibiotic therapy and anti-shock therapy, direct hemoperfusion using polymyxin B immobilized fiber column (PMX) was carried out. Thereafter, cardiovascular instabilities were improved without increasing the supply of catecholamines. PMX therapy for systemic inflammatory response due to infection was effective in treatment of cardiovascular instabilities.