A lytic bacteriophage isolated from sewage water was found to attack drugresistant Klebsiella pneumoniae DR1 isolated from a clinical specimen. The phage, designated kpdr1, had an isomeric head (60 nm in diameter) with a contractile tail (93 nm long and 13 nm wide). It was identified in Myoviridae family. From the host range test, the phage was highly specific to K. pneumoniae DR1. A onestep growth experiment of phage kpdr1 at 37 C after the phage infection showed that the latent period was 30 min, the burst period was 180 min, and the average burst size was about 52 phage particles/infected cell. The phage was able to survive after incubating at 37 C for 24 h in pH 5-12. The phage was also stable at the temperature of 60 C for at least 3 min. Various disinfectants could inactivate the phage after treating at 37 C for 24 h. Knowledge of the properties of K. pneumoniae DR1 bacteriophage kpdr1 may be important for the development of controlled infection.