The importance of meteorologic factors on cerebrovascular accidents has been somewhat overshadowed by the overwhelming clinical and pathological studies on them. The present study was accomplished on the deaths from 1, 075 cerebral hemorrhage, 527 cerebral infarction and 46 subarachnoid hemorrhage in connection with various meteorologic factors including their values, gradients, variations of gradient and some indicators of combined meteorologic effects. The excess deaths at low air and Missenard's effective temperature, at low and high temperature-humidity index, at the increase of relative humidity and at the decrease of atmospheric pressure, and the fewer deaths at moderate air and Missenard's effective temperature, at low atmospheric pressure and at moderate temperature-humidity index were revealed. These findings were generally more conspicuous in males and 70 years or more of age. Furthermore, the effects of the variations of gradient of meteorologic factors were also recognized. Relative evaluations of these effects with careful considerations of various ecological factors were emphasized.