Primary aldosteronism is characterized by hypertension, suppressed plasma renin activity, increased aldosterone excretion, and hypokalemia. Although muscle weakness is a well-known muscular manifestation of marked hypokalemia with primary aldosteronism, both rhabdomyolysis and hypokalemic periodic paralysis are rare presentations respectively. Moreover, simultaneous occurrence of these two complications in primary aldosteronism is much rarer. We report a case of a 52-year-old man, who presented with muscular paralysis, hypertension, and hypokalemia. On admission, his plasma potassium level was 2.3 mmol/L and creatinine kinase level was 1815.0 IU/L. The diagnosis of hypokalemic periodic paralysis was confirmed by electromyography and nerve conduction velocity. Aldosterone-renin ratio (ng/dL÷ng/mL/hr) was 76.9 and subsequent computed tomographic evaluation of right adrenal gland revealed 1.1 cm-sized nodule. Thereafter, laparoscopic removal of adrenal nodule was performed and adrenal gland adenoma was pathologically confirmed. Several weeks after surgery, the patient``s blood pressure and plasma potassium level were restored within normal range without medications. This case suggests that, if primary aldosteronism is presented, serious muscular complications such as hypokalemic periodic paralysis and rhabdomyolysis, individually or together, masked by muscular weakness, which is common in hypokalemia, should be considered.