OBJECTIVE:To study the membranous and structure changes of type Ⅰ alveolar cells in diabetic ketoacidosis rabbit models. METHODS: 12 male New Zealand rabbits were divided into experimental groups (DK groups, n=6) and control groups (NS groups, n=6) randomly; Injection of streptozocin (150mg/kg) and alloxan monohydroate (150mg/kg) each in DK groups were received by i.v, and NS groups were given the same dose normal sodium chloride. blood gas, blood electrolyte and urine acetone body were detected; All the animals were killed 72 hours later, blood gas,alkaline phosphates (ALPase) of cytohistochemical examination, ultrastructure were detected. RESULTS: Plasma glucose concentration values were >17 mmol/L and urine acetone body appeared in all DK groups, thickening of the alveolar basement membrane and air-blood barrier, inflammatory cellular exudation were shown in DK groups. The activity of alkaline phosphates was lost in type Ⅰ alveolar cells. Type Ⅰalveolar cell and capillary endothelium damages were observed. No changes were shown in NS groups. CONCLUSION: DKA induce type Ⅰ alveolar cells lesion, membranous structure spoiled occupy important action.