Experiments were performed on spontaneously breathing rabbits anesthetized with urethan. The diaphragmatic fatigue (DiF) was reproduced by the phrenic nerve stimulation (30 Hz, 10 V,0. 2 ms). The transdiaphragmatic pressure (Pdi) and diaphragm evoked potential (DEP) were measured before injury and after injury 30, 60, 90, and 120 min. Pdimax and the amplitude of DEP obviously decreased and the latency of DEP obviously delayed after injury 30min. The amplitude of Pdi and DEP were quickly promoted by introvenous injection of neostig-mine after DiF. The latency of DEP was partially recovered by introvenous injection of neostig-mine. It is concluded that neostigmine can improve the generation of the fatigued diaphragm. and promote its recovery.