<正> This study was designed to observe the dynamic changes of plateletaggregation with Born’s method and serum fibrin degradation products（FDP）with staphy lococcus clumping test after smoke inhalation in rabbits.Pathological studies of the lung tissues and determination of the lung water werealso carried out after the animals were killed.It was found that there was marked increase of the platelet aggregation ratein the 2nd and 10th hour postburn（PB）

and the platelet count decreasedprogressively after injury.FDP increased in the 6th and 24th hour PB.Pathologically

there were congestion

interstitial edema and alveolar hemorrhageand edema in the lungs.Under electron microscope

it was found that plateletaggregation occurred in the lumen of small pulmonary vessels.Most plateletswere deformed with evacuation of their granules.In addition

the lung watercontent increased apparently.In association with these changes

the animalsexhibited difficulty in breathing and rales over the chest.On the basis of our obervation

it is thus proposed that the changes ofplatelets and FDP may play important roles in the development of pulmonaryedema after smoke inhalation.