Four cases of carpal tunnel syndrome in acromegaly were reported. These 4 cases were found in 21 acromegalies (19%). Besides change of features, they complained bilateral sensory disturbances of their hands. After transsphenoidal removal of pituitary adenoma, GH levels returned to the normal range and sensory disturbances were improved in all cases. Mechanism of carpal tunnel syndrome in acromegaly is that edematous synovial tissues compress the median nerve because oversecretion of growth hormone causes increase of sodium and water retention in the extracellular fluid. The patient who showes high basal level of growth hormone and/or acromegalic pattern by various tolerance tests does not always have the carpal tunnel syndrome. But this syndrome is apt to be found in active acromegaly. So the detection of the symptom showed by this activity such as hypersudation in our cases leads to the early diagnosis of acromegaly.