An atypical form of chronic inflammatory demyelinating polyneuropathy (CIDP) complicated with phrenic nerve palsy is presented with clinical and electrophysiologic features. A seven-year-old girl had initial presentation mimicking Guillain-Barré syndrome based on electrophysiologic characteristics. Between 7-11 years of age, she had five recurrences of subacute onset of weakness which usually developed over at least 2-4 months and progressed to loss of ambulation and to respiratory insufficiency. Radiologic examinations revealed unilateral phrenic nerve palsy associated with CIDP. Our patient demonstrated the rare association of CIDP and phrenic nerve palsy, resulting in diaphragmatic paralysis and respiratory failure.