Inhaled drug is one of the most effective ways to treat various diseases.Kanamycin is an aminoglycoside antibiotic and effective against a broad spectrum of Gram-positive and Gram-negative bacteria.The physical and antibiotic properties of kanamycin obtained by spray freeze drying (SFD) were compared with those of kanamycin itself.Also,SFD procedures of kanamycin were optimized to prepare kanamycin to an inhaled drug.Scanning electron microscopy (SEM) and laser particle size analyzer were applied for estimate physical structure and properties.