Abstract: Studies have been conducted to determine whether nikethamide may be effectively and safely absorbed through the endotracheal route in the canine model. As the results, one and half（1.5）minutes after administration of nikethamide the difference of drug concentration following the intravenous and endotracheal route （8.3mg/kg） was not significant. However, the blood concentration of nikethamide is increased when the endotracheal dose was inereasesed, 50% being absorbed 0.48 minutes after endotracheal administration. Bioavailability is 84.69%. The frequency of breath and tidal volume were increased after the administration of nikethamide. These results suggest that endotracheal application of nikethamide can produce the similar effects as through the intravenous route.